{"topic":"hydride-superconductors","sort":"top","limit":25,"offset":0,"count":25,"papers":[{"id":"arxiv:1506.08190","kind":"article","title":"Conventional superconductivity at 203 kelvin at high pressures in the sulfur hydride system","authors":["Alexander P. Drozdov","M. I. Eremets","Ivan A. Troyan","Vadim Ksenofontov","Sergii I. Shylin"],"author_count":5,"year":2015,"published":"2015-08-17","venue":"Nature","cited_by":2753,"doi":"10.1038/nature14964","arxiv_id":"1506.08190","nct_id":null,"source_url":"https://doi.org/10.1038/nature14964","archive_url":"https://space-kitty.com/papers/arxiv:1506.08190","updated":"2015-06-26","pmid":"26280333","pmcid":null,"openalex_id":"W1668507869","pdf_url":"https://arxiv.org/pdf/1506.08190","abstract":"A superconductor is a material that can conduct electricity with no resistance below its critical temperature (Tc). The highest Tc that has been achieved in cuprates1 is 133 K at ambient pressure2 and 164 K at high pressures3. As the nature of superconductivity in these materials has still not been explained, the prospects for a higher Tc are not clear. In contrast, the Bardeen-Cooper-Schrieffer (BCS) theory gives a guide for achieving high Tc and does not put bounds on Tc, all that is needed is a favorable combination of high frequency phonons, strong electron-phonon coupling, and a high density of states. These conditions can be fulfilled for metallic hydrogen and covalent compounds dominated by hydrogen4,5. Numerous calculations support this idea and predict Tc of 50-235 K for many hydrides6 but only moderate Tc=17 K has been observed experimentally7. Here we studied sulfur hydride8 where a Tc~80 K was predicted9. We found that it transforms to a metal at pressure ~90 GPa. With cooling superconductivity was found deduced from a sharp drop of the resistivity to zero and a decrease of Tc with magnetic field. The pronounce isotope shift of Tc in D2S is evidence of an electron-phonon mechanism of superconductivity that is consistent with the BCS scenario. The superconductivity has been confirmed by magnetic susceptibility measurements with Tc=203K. The high Tc superconductivity most likely is due to H3S which is formed from H2S under its decomposition under pressure. Even higher Tc, room temperature superconductivity, can be expected in other hydrogen-based materials since hydrogen atoms provide the high frequency phonon modes as well as the strong electron-phonon coupling.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1812.01561","kind":"article","title":"Superconductivity at 250 K in lanthanum hydride under high pressures","authors":["A. P. Drozdov","P. P. Kong","V. S. Minkov","S. P. Besedin","M. A. Kuzovnikov","S. Mozaffari","L. Balicas","F. Balakirev","D. Graf","V. B. Prakapenka","E. Greenberg","D. A. Knyazev","M. Tkacz","M. I. Eremets"],"author_count":14,"year":2018,"published":"2018-12-04","venue":"Nature","cited_by":1644,"doi":"10.1038/s41586-019-1201-8","arxiv_id":"1812.01561","nct_id":null,"source_url":"https://arxiv.org/abs/1812.01561","archive_url":"https://space-kitty.com/papers/arxiv:1812.01561","updated":"2018-12-04","pmid":"31118520","pmcid":null,"openalex_id":"W2902694017","pdf_url":"https://arxiv.org/pdf/1812.01561","abstract":"The discovery of superconductivity at 203 K in H3S brought attention back to conventional superconductors whose properties can be described by the Bardeen-Cooper-Schrieffer (BCS) and the Migdal-Eliashberg theories. These theories predict that high, and even room temperature superconductivity (RTSC) is possible in metals possessing certain favorable parameters such as lattice vibrations at high frequencies. However, these general theories do not suffice to predict real superconductors. New superconducting materials can be predicted now with the aid of first principles calculations based on Density Functional Theory (DFT). In particular, the calculations suggested a new family of hydrides possessing a clathrate structure, where the host atom (Ca, Y, La) is at the center of the cage formed by hydrogen atoms. For LaH10 and YH10 superconductivity, with critical temperatures Tc ranging between 240 and 320 K is predicted at megabar pressures. Here, we report superconductivity with a record Tc ~ 250 K within the Fm-3m structure of LaH10 at a pressure P ~ 170 GPa. We proved the existence of superconductivity at 250 K through the observation of zero-resistance, isotope effect, and the decrease of Tc under an external magnetic field, which suggests an upper critical magnetic field of 120 T at zero-temperature. The pressure dependence of the transition temperatures Tc (P) has a maximum of 250-252 K at the pressure of about 170 GPa. This leap, by ~ 50 K, from the previous Tc record of 203 K indicates the real possibility of achieving RTSC (that is at 273 K) in the near future at high pressures and the perspective of conventional superconductivity at ambient pressure.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["cond-mat.supr-con"],"details":null,"provenance":"arxiv+openalex","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"doi:10.1038/srep06968","kind":"article","title":"Pressure-induced metallization of dense (H2S)2H2 with high-Tc superconductivity","authors":["Defang Duan","Yunxian Liu","Fubo Tian","Da Li","Xiaoli Huang","Zhonglong Zhao","Hongyu Yu","Bingbing Liu","Wenjing Tian","Tian Shu Cui"],"author_count":10,"year":2014,"published":"2014-11-10","venue":"Scientific Reports","cited_by":1175,"doi":"10.1038/srep06968","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1038/srep06968","archive_url":"https://space-kitty.com/papers/doi:10.1038/srep06968","updated":null,"pmid":"25382349","pmcid":null,"openalex_id":"W1963957450","pdf_url":"https://www.nature.com/articles/srep06968.pdf","abstract":null,"abstract_license":null,"license":"cc-by-nc-sa","is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"doi:10.1073/pnas.1704505114","kind":"article","title":"Potential high- T c superconducting lanthanum and yttrium hydrides at high pressure","authors":["Hanyu Liu","Ivan I. Naumov","Roald Hoffmann","Neil William Ashcroft","Russell J. Hemley"],"author_count":5,"year":2017,"published":"2017-06-19","venue":"Proceedings of the National Academy of Sciences","cited_by":1065,"doi":"10.1073/pnas.1704505114","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1073/pnas.1704505114","archive_url":"https://space-kitty.com/papers/doi:10.1073/pnas.1704505114","updated":null,"pmid":"28630301","pmcid":null,"openalex_id":"W2681350253","pdf_url":null,"abstract":null,"abstract_license":null,"license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"doi:10.1103/physrevlett.119.107001","kind":"article","title":"Hydrogen Clathrate Structures in Rare Earth Hydrides at High Pressures: Possible Route to Room-Temperature Superconductivity","authors":["Feng Peng","Ying Sun","Chris J. Pickard","Richard J. Needs","Qiang Wu","Yanming Ma"],"author_count":6,"year":2017,"published":"2017-09-08","venue":"Physical Review Letters","cited_by":959,"doi":"10.1103/physrevlett.119.107001","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1103/physrevlett.119.107001","archive_url":"https://space-kitty.com/papers/doi:10.1103/physrevlett.119.107001","updated":null,"pmid":"28949166","pmcid":null,"openalex_id":"W2753773550","pdf_url":null,"abstract":null,"abstract_license":null,"license":null,"is_open_access":false,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"arxiv:1203.0263","kind":"article","title":"Superconductive sodalite-like clathrate calcium hydride at high pressures","authors":["Hui Wang","John S. Tse","Kaori Tanaka","Toshiaki Iitaka","Yanming Ma"],"author_count":5,"year":2012,"published":"2012-04-06","venue":"Proceedings of the National Academy of Sciences","cited_by":926,"doi":"10.1073/pnas.1118168109","arxiv_id":"1203.0263","nct_id":null,"source_url":"https://doi.org/10.1073/pnas.1118168109","archive_url":"https://space-kitty.com/papers/arxiv:1203.0263","updated":"2012-03-01","pmid":"22492976","pmcid":null,"openalex_id":"W2082187021","pdf_url":"https://arxiv.org/pdf/1203.0263","abstract":"Hydrogen-rich compounds hold promise as high-temperature superconductors under high pressures. Recent theoretical hydride structures on achieving high-pressure superconductivity are composed mainly of H2 fragments. Through a systematic investigation of Ca hydrides with different hydrogen contents using particle-swam optimization structural search, we show that in the stoichiometry CaH6 a body-centred cubic structure with hydrogen that forms unusual \"sodalite\" cages containing enclathrated Ca stabilizes above pressure 150 GPa. The stability of this structure is derived from the acceptance by two H2 of electrons donated by Ca forming a \"H4\" unit as the building block in the construction of the 3-dimensional sodalite cage. This unique structure has a partial occupation of the degenerated orbitals at the zone centre. The resultant dynamic Jahn-Teller effect helps to enhance electron-phonon coupling and leads to superconductivity of CaH6. A superconducting critical temperature (Tc) of 220-235 K at 150 GPa obtained from the solution of the Eliashberg equations is the highest among all hydrides studied thus far.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"doi:10.1038/s41467-021-25372-2","kind":"article","title":"Superconductivity up to 243 K in the yttrium-hydrogen system under high pressure","authors":["P. P. Kong","Vasily S. Minkov","Mikhail A. Kuzovnikov","Alexander P. Drozdov","Stanislav P. Besedin","Shirin Mozaffari","Luis Balicas","Fedor Balakirev","Vitali B. Prakapenka","Stella Chariton","Dmitry A. Knyazev","Eran Greenberg","M. I. Eremets"],"author_count":13,"year":2021,"published":"2021-08-20","venue":"Nature Communications","cited_by":534,"doi":"10.1038/s41467-021-25372-2","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1038/s41467-021-25372-2","archive_url":"https://space-kitty.com/papers/doi:10.1038/s41467-021-25372-2","updated":null,"pmid":"34417471","pmcid":null,"openalex_id":"W3194629154","pdf_url":"https://www.nature.com/articles/s41467-021-25372-2.pdf","abstract":"Abstract The discovery of superconducting H 3 S with a critical temperature T c ∼200 K opened a door to room temperature superconductivity and stimulated further extensive studies of hydrogen-rich compounds stabilized by high pressure. Here, we report a comprehensive study of the yttrium-hydrogen system with the highest predicted T c s among binary compounds and discuss the contradictions between different theoretical calculations and experimental data. We synthesized yttrium hydrides with the compositions of YH 3 , YH 4 , YH 6 and YH 9 in a diamond anvil cell and studied their crystal structures, electrical and magnetic transport properties, and isotopic effects. We found superconductivity in the Im-3m YH 6 and P6 3 /mmc YH 9 phases with maximal T c s of ∼220 K at 183 GPa and ∼243 K at 201 GPa, respectively. Fm-3m YH 10 with the highest predicted T c > 300 K was not observed in our experiments, and instead, YH 9 was found to be the hydrogen-richest yttrium hydride in the studied pressure and temperature range up to record 410 GPa and 2250 K.","abstract_license":"CC-BY (publisher license, via OpenAlex)","license":"cc-by","is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Abstract of \"Superconductivity up to 243 K in the yttrium-hydrogen system under high pressure\" by P. P. Kong, Vasily S. Minkov, Mikhail A. Kuzovnikov et al., https://doi.org/10.1038/s41467-021-25372-2, used under its Creative Commons Attribution license (CC-BY); markup removed, otherwise unmodified."},{"id":"doi:10.1103/physrevlett.128.167001","kind":"article","title":"High-Temperature Superconducting Phase in Clathrate Calcium Hydride CaH 6 up to 215 K at a Pressure of 172 GPa","authors":["Liang Ma","Kui Wang","Yu Xie","Xin Yang","Yingying Wang","Mi Zhou","Hanyu Liu","Xiaohui Yu","Yongsheng Zhao","Hongbo Wang","Guangtao Liu","Yanming Ma"],"author_count":12,"year":2022,"published":"2022-04-20","venue":"Physical Review Letters","cited_by":477,"doi":"10.1103/physrevlett.128.167001","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1103/physrevlett.128.167001","archive_url":"https://space-kitty.com/papers/doi:10.1103/physrevlett.128.167001","updated":null,"pmid":"35522494","pmcid":null,"openalex_id":"W4224231208","pdf_url":"http://link.aps.org/pdf/10.1103/PhysRevLett.128.167001","abstract":null,"abstract_license":null,"license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"openalex:W3098955174","kind":"article","title":"Superconductivity at 250 K in lanthanum hydride under high pressures","authors":["Alexander P. Drozdov","P. P. Kong","Vasily S. Minkov","Stanislav P. Besedin","Mikhail A. Kuzovnikov","Shirin Mozaffari","Luis Balicas","Fedor Balakirev","David E Graf","Vitali B. Prakapenka","Eran Greenberg","D. A. Knyazev","M. Tkacz","M. I. Eremets"],"author_count":14,"year":2019,"published":"2019-01-01","venue":"RePEc: Research Papers in Economics","cited_by":539,"doi":null,"arxiv_id":null,"nct_id":null,"source_url":"https://www.nature.com/articles/s41586-019-1201-8","archive_url":"https://space-kitty.com/papers/openalex:W3098955174","updated":null,"pmid":null,"pmcid":null,"openalex_id":"W3098955174","pdf_url":null,"abstract":null,"abstract_license":null,"license":null,"is_open_access":false,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"arxiv:1905.06693","kind":"article","title":"A perspective on conventional high-temperature superconductors at high pressure: Methods and materials","authors":["José A. Flores‐Livas","Lilia Boeri","Antonio Sanna","Gianni Profeta","Ryotaro Arita","Mikhail Eremets"],"author_count":6,"year":2020,"published":"2020-02-15","venue":"Physics Reports","cited_by":530,"doi":"10.1016/j.physrep.2020.02.003","arxiv_id":"1905.06693","nct_id":null,"source_url":"https://doi.org/10.1016/j.physrep.2020.02.003","archive_url":"https://space-kitty.com/papers/arxiv:1905.06693","updated":"2020-01-22","pmid":null,"pmcid":null,"openalex_id":"W3005669342","pdf_url":"https://arxiv.org/pdf/1905.06693","abstract":"Two hydrogen-rich materials, H$_3$S and LaH$_{10}$, synthesized at megabar pressures, have revolutionized the field of condensed matter physics providing the first glimpse to the solution of the hundred-year-old problem of room temperature superconductivity. The mechanism underlying superconductivity in these exceptional compounds is the conventional electron-phonon coupling. Here we describe recent advances in experimental techniques, superconductivity theory and first-principles computational methods which have made possible these discoveries. This work aims to provide an up-to-date compendium of the available results on superconducting hydrides and explain how the synergy of different methodologies led to extraordinary discoveries in the field. Besides, in an attempt to evidence empirical rules governing superconductivity in binary hydrides under pressure, we discuss general trends in the electronic structure and chemical bonding. The last part of the Review introduces possible strategies to optimize pressure and transition temperatures in conventional superconducting materials as well as future directions in theoretical, computational and experimental research.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":"cc-by","is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1908.01534","kind":"article","title":"Anomalous High‐Temperature Superconductivity in YH 6","authors":["Ivan A. Troyan","Dmitrii V. Semenok","Alexander G. Kvashnin","A. V. Sadakov","O. A. Sobolevskiy","V. M. Pudalov","Anna Gennadievna Ivanova","Vitali B. Prakapenka","Eran Greenberg","Alexander G. Gavriliuk","Igor S Lyubutin","Viktor V. Struzhkin","Aitor Bergara","Ion Errea","Raffaello Bianco","Matteo Calandra","Francesco Mauri","Lorenzo Monacelli","Ryosuke Akashi","Артем Ромаевич Оганов"],"author_count":20,"year":2021,"published":"2021-03-10","venue":"Advanced Materials","cited_by":472,"doi":"10.1002/adma.202006832","arxiv_id":"1908.01534","nct_id":null,"source_url":"https://doi.org/10.1002/adma.202006832","archive_url":"https://space-kitty.com/papers/arxiv:1908.01534","updated":"2020-06-12","pmid":"33751670","pmcid":null,"openalex_id":"W3134814034","pdf_url":"https://arxiv.org/pdf/1908.01534","abstract":"Pressure-stabilized hydrides are a new rapidly growing class of high-temperature superconductors which is believed to be described within the conventional phonon-mediated mechanism of coupling. Here we report the synthesis of yttrium hexahydride Im3m-YH$_6$ that demonstrates the superconducting transition with T$_c$ = 224 K at 166 GPa, much lower than the theoretically predicted (>270 K). The measured upper critical magnetic field B$_c$$_2$(0) of YH$_6$ was found to be 116-158 T, which is 2-2.5 times larger than the calculated value. A pronounced shift of T$_c$ in yttrium deuteride YD$_6$ with the isotope coefficient 0.4 supports the phonon-assisted superconductivity. Current-voltage measurements showed that the critical current I$_c$ and its density J$_c$ may exceed 1.75 A and 3500 A/mm$^2$ at 0 K, respectively, which is comparable with the parameters of commercial superconductors, such as NbTi and YBCO. The superconducting density functional theory (SCDFT) and anharmonic calculations suggest unusually large impact of the Coulomb repulsion in this compound. The results indicate notable departures of the superconducting properties of the discovered YH$_6$ from the conventional Migdal-Eliashberg and Bardeen-Cooper-Schrieffer theories.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:2012.04787","kind":"article","title":"Superconductivity at 253 K in lanthanum-yttrium ternary hydrides","authors":["Dmitrii V. Semenok","Ivan A. Troyan","Alexander G. Kvashnin","Anna G. Ivanova","Michael Hanfland","Andrey V. Sadakov","Oleg A. Sobolevskiy","Kirill S. Pervakov","Alexander G. Gavriliuk","Igor S. Lyubutin","Konstantin V. Glazyrin","Nico Giordano","Denis N. Karimov","Alexander B. Vasiliev","Ryosuke Akashi","Vladimir M. Pudalov","Artem R. Oganov"],"author_count":17,"year":2020,"published":"2020-12-08","venue":"Materials Today, 2021","cited_by":288,"doi":"10.1016/j.mattod.2021.03.025","arxiv_id":"2012.04787","nct_id":null,"source_url":"https://arxiv.org/abs/2012.04787","archive_url":"https://space-kitty.com/papers/arxiv:2012.04787","updated":"2020-12-08","pmid":null,"pmcid":null,"openalex_id":"W3113234112","pdf_url":"https://arxiv.org/pdf/2012.04787","abstract":"Polyhydrides offer intriguing perspectives as high-temperature superconductors. Here we report the high-pressure synthesis of a series of lanthanum-yttrium ternary hydrides: cubic hexahydride $(La,Y)H_{6}$ with a critical temperature $T_{C}$ = 237 +/- 5 K and decahydrides $(La,Y)H_{10}$ with a maximum $T_{C}$ ~${253 K}$ and an extrapolated upper critical magnetic field $B_{C2(0)}$ up to ${135 T}$ at 183 GPa. This is one of the first examples of ternary high-$T_{C}$ superconducting hydrides. Our experiments show that a part of the atoms in the structures of recently discovered ${Im3m}$-$YH_{6}$ and ${Fm3m}$-$LaH_{10}$ can be replaced with lanthanum (~70 %) and yttrium (~25 %), respectively, with a formation of unique ternary superhydrides containing incorporated $La@H_{24}$ and $Y@H_{32}$ which are specific for ${Im3m}$-$LaH_{6}$ and ${Fm3m}$-$YH_{10}$. Ternary La-Y hydrides were obtained at pressures of 170-196 GPa via the laser heating of $P6_{3}$${/mmc}$ lanthanum-yttrium alloys in the ammonia borane medium at temperatures above 2000 K. A novel tetragonal $(La,Y)H_{4}$ was discovered as an impurity phase in synthesized cubic $(La,Y)H_{6}$. The current-voltage measurements show that the critical current density $J_{C}$ in $(La,Y)H_{10}$ may exceed $2500 A/mm^{2}$ at 4.2 K, which is comparable with that for commercial superconducting wires such as ${NbTi}$, $Nb_{3}$${Sn}$. Hydrides that are unstable in a pure form may nevertheless be stabilized at relatively low pressures in solid solutions with superhydrides having the same structure.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["cond-mat.supr-con"],"details":null,"provenance":"arxiv+openalex","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:2103.16917","kind":"article","title":"Superconductivity above 200 K Observed in Superhydrides of Calcium","authors":["Z. Li","X. He","C. L. Zhang","X. C. Wang","S. J. Zhang","Y. T. Jia","S. M. Feng","K. Lu","J. F. Zhao","J. Zhang","B. S. Min","Y. W. Long","R. C. Yu","L. H. Wang","M. Y. Ye","Z. S. Zhang","V. Prakapenka","S. Chariton","P. A. Ginsberg","J. Bass","S. H. Yuan","H. Z. Liu","C. Q. Jin"],"author_count":23,"year":2021,"published":"2021-03-31","venue":"Nature Communications 13, 2863 (2022)","cited_by":290,"doi":"10.1038/s41467-022-30454-w","arxiv_id":"2103.16917","nct_id":null,"source_url":"https://arxiv.org/abs/2103.16917","archive_url":"https://space-kitty.com/papers/arxiv:2103.16917","updated":"2022-06-09","pmid":"35606357","pmcid":null,"openalex_id":"W4281288168","pdf_url":"https://arxiv.org/pdf/2103.16917","abstract":"Searching for superconductivity with Tc near room temperature is of great interest both for fundamental science & many potential applications. Here we report the experimental discovery of superconductivity with maximum critical temperature (Tc) above 210 K in calcium superhydrides, the new alkali earth hydrides experimentally showing superconductivity above 200 K in addition to sulfur hydride & rare-earth hydride system. The materials are synthesized at the synergetic conditions of 160~190 GPa and ~2000 K using diamond anvil cell combined with in-situ laser heating technique. The superconductivity was studied through in-situ high pressure electric conductance measurements in an applied magnetic field for the sample quenched from high temperature while maintained at high pressures. The upper critical field Hc(0) was estimated to be ~268 T while the GL coherent length is ~11 angstrom. The in-situ synchrotron X-ray diffraction measurements suggest that the synthesized calcium hydrides are primarily composed of CaH6 while there may also exist other calcium hydrides with different hydrogen contents.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":"cc-by","is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["cond-mat.supr-con","cond-mat.mtrl-sci","cond-mat.str-el"],"details":null,"provenance":"arxiv+openalex","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"doi:10.1103/physrevlett.123.097001","kind":"article","title":"Route to a Superconducting Phase above Room Temperature in Electron-Doped Hydride Compounds under High Pressure","authors":["Ying Sun","Jian Lv","Yu Xie","Hanyu Liu","Yanming Ma"],"author_count":5,"year":2019,"published":"2019-08-26","venue":"Physical Review Letters","cited_by":453,"doi":"10.1103/physrevlett.123.097001","arxiv_id":null,"nct_id":null,"source_url":"https://doi.org/10.1103/physrevlett.123.097001","archive_url":"https://space-kitty.com/papers/doi:10.1103/physrevlett.123.097001","updated":null,"pmid":"31524448","pmcid":null,"openalex_id":"W2971173954","pdf_url":null,"abstract":null,"abstract_license":null,"license":null,"is_open_access":false,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"openalex:W3104116474","kind":"article","title":"A perspective on conventional high-temperature superconductors at high pressure: Methods and materials","authors":["Flores-Livas, J.","Boeri, L.","Sanna, A.","Profeta, G.","Arita, R.","Eremets, M."],"author_count":6,"year":2020,"published":"2020-04-29","venue":"MPG.PuRe (Max Planck Society)","cited_by":430,"doi":null,"arxiv_id":null,"nct_id":null,"source_url":"http://hdl.handle.net/21.11116/0000-0007-4D59-0","archive_url":"https://space-kitty.com/papers/openalex:W3104116474","updated":null,"pmid":null,"pmcid":null,"openalex_id":"W3104116474","pdf_url":null,"abstract":null,"abstract_license":null,"license":null,"is_open_access":false,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"arxiv:2101.01315","kind":"article","title":"High-Temperature Superconductivity in Cerium Superhydrides","authors":["Wuhao Chen","Dmitrii V. Semenok","Xiaoli Huang","Haiyun Shu","Xin Li","Defang Duan","Tian Cui","Artem R. Oganov"],"author_count":8,"year":2021,"published":"2021-01-05","venue":"Phys. Rev. Lett. 127, 117001 (2021)","cited_by":277,"doi":"10.1103/physrevlett.127.117001","arxiv_id":"2101.01315","nct_id":null,"source_url":"https://arxiv.org/abs/2101.01315","archive_url":"https://space-kitty.com/papers/arxiv:2101.01315","updated":"2021-01-06","pmid":"34558917","pmcid":null,"openalex_id":"W3119189107","pdf_url":"https://arxiv.org/pdf/2101.01315","abstract":"The discoveries of high-temperature superconductivity in H3S and LaH10 have excited the search for superconductivity in compressed hydrides. In contrast to rapidly expanding theoretical studies, high-pressure experiments on hydride superconductors are expensive and technically challenging. Here we experimentally discover superconductivity in two new phases,Fm-3m-CeH10 (SC-I phase) and P63/mmc-CeH9 (SC-II phase) at pressures that are much lower (<100 GPa) than those needed to stabilize other polyhydride superconductors. Superconductivity was evidenced by a sharp drop of the electrical resistance to zero, and by the decrease of the critical temperature in deuterated samples and in an external magnetic field. SC-I has Tc=115 K at 95 GPa, showing expected decrease on further compression due to decrease of the electron-phonon coupling (EPC) coefficient λ (from 2.0 at 100 GPa to 0.8 at 200 GPa). SC-II has Tc = 57 K at 88 GPa, rapidly increasing to a maximum Tc ~100 K at 130 GPa, and then decreasing on further compression. This maximum of Tc is due to a maximum of λ at the phase transition from P63/mmc-CeH9 into a symmetry-broken modification C2/c-CeH9. The pressure-temperature conditions of synthesis affect the actual hydrogen content, and the actual value of Tc. Anomalously low pressures of stability of cerium superhydrides make them appealing for studies of superhydrides and for designing new superhydrides with even lower pressures of stability.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["cond-mat.supr-con","cond-mat.mtrl-sci"],"details":null,"provenance":"arxiv+openalex","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1907.11916","kind":"article","title":"Quantum crystal structure in the 250-kelvin superconducting lanthanum hydride","authors":["Ion Errea","Francesco Belli","Lorenzo Monacelli","Antonio Sanna","Takashi Koretsune","Terumasa Tadano","Raffaello Bianco","Matteo Calandra","Ryotaro Arita","Francesco Mauri","José A. Flores‐Livas"],"author_count":11,"year":2020,"published":"2020-02-05","venue":"Nature","cited_by":356,"doi":"10.1038/s41586-020-1955-z","arxiv_id":"1907.11916","nct_id":null,"source_url":"https://doi.org/10.1038/s41586-020-1955-z","archive_url":"https://space-kitty.com/papers/arxiv:1907.11916","updated":"2019-07-27","pmid":"32025016","pmcid":null,"openalex_id":"W3005295643","pdf_url":"https://arxiv.org/pdf/1907.11916","abstract":"The discovery of superconductivity at 200 K in the hydrogen sulfide system at large pressures [1] was a clear demonstration that hydrogen-rich materials can be high-temperature superconductors. The recent synthesis of LaH$_{10}$ with a superconducting critical temperature (T$_{\\text{c}}$) of 250 K [2,3] places these materials at the verge of reaching the long-dreamed room-temperature superconductivity. Electrical and x-ray diffraction measurements determined a weakly pressure-dependent T$_{\\text{c}}$ for LaH$_{10}$ between 137 and 218 gigapascals in a structure with a face-centered cubic (fcc) arrangement of La atoms [3]. Here we show that quantum atomic fluctuations stabilize in all this pressure range a high-symmetry Fm-3m crystal structure consistent with experiments, which has a colossal electron-phonon coupling of $λ\\sim3.5$. Even if ab initio classical calculations neglecting quantum atomic vibrations predict this structure to distort below 230 GPa yielding a complex energy landscape with many local minima, the inclusion of quantum effects simplifies the energy landscape evidencing the Fm-3m as the true ground state. The agreement between the calculated and experimental T$_{\\text{c}}$ values further supports this phase as responsible for the 250 K superconductivity. The relevance of quantum fluctuations in the energy landscape found here questions many of the crystal structure predictions made for hydrides within a classical approach that at the moment guide the experimental quest for room-temperature superconductivity [4,5,6]. Furthermore, quantum effects reveal crucial to sustain solids with extraordinary electron-phonon coupling that may otherwise be unstable [7].","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1902.10206","kind":"article","title":"Superconductivity at 161 K in thorium hydride ThH10: Synthesis and properties","authors":["Dmitrii V. Semenok","Alexander G. Kvashnin","Anna Gennadievna Ivanova","Volodymyr Svitlyk","Vyacheslav Yu. Fominski","A. V. Sadakov","O. A. Sobolevskiy","V. M. Pudalov","Ivan A. Troyan","Артем Ромаевич Оганов"],"author_count":10,"year":2019,"published":"2019-11-06","venue":"Materials Today","cited_by":316,"doi":"10.1016/j.mattod.2019.10.005","arxiv_id":"1902.10206","nct_id":null,"source_url":"https://doi.org/10.1016/j.mattod.2019.10.005","archive_url":"https://space-kitty.com/papers/arxiv:1902.10206","updated":"2019-11-22","pmid":null,"pmcid":null,"openalex_id":"W2988132421","pdf_url":"https://arxiv.org/pdf/1902.10206","abstract":"Here we report targeted high-pressure synthesis of two novel high-$T_C$ hydride superconductors, $P6_3/mmc$-$ThH_9$ and $Fm\\bar{3}m$-$ThH_{10}$, with the experimental critical temperatures ($T_C$) of 146 K and 159-161 K and upper critical magnetic fields ($μ$$H_C$) 38 and 45 Tesla at pressures 170-175 Gigapascals, respectively. Superconductivity was evidenced by the observation of zero resistance and a decrease of $T_C$ under external magnetic field up to 16 Tesla. This is one of the highest critical temperatures that has been achieved experimentally in any compounds, along with such materials as $LaH_{10}$, $H_3S$ and $HgBa_2Ca_xCu_2O_{6+z}$. Our experiments show that $fcc$-$ThH_{10}$ has stabilization pressure of 85 GPa, making this material unique among all known high-$T_C$ metal polyhydrides. Two recently predicted Th-H compounds, $I4/mmm$-$ThH_4$ (> 86 GPa) and $Cmc2_1$-$ThH_6$ (86-104 GPa), were also synthesized. Equations of state of obtained thorium polyhydrides were measured and found to perfectly agree with the theoretical calculations. New phases were examined theoretically and their electronic, phonon, and superconducting properties were calculated.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1512.02933","kind":"article","title":"Quantum hydrogen-bond symmetrization in the superconducting hydrogen sulfide system","authors":["Ion Errea","Matteo Calandra","Chris J. Pickard","J. Nelson","Richard J. Needs","Yinwei Li","Hanyu Liu","Yunwei Zhang","Yanming Ma","Francesco Mauri"],"author_count":10,"year":2016,"published":"2016-03-24","venue":"Nature","cited_by":331,"doi":"10.1038/nature17175","arxiv_id":"1512.02933","nct_id":null,"source_url":"https://doi.org/10.1038/nature17175","archive_url":"https://space-kitty.com/papers/arxiv:1512.02933","updated":"2015-12-09","pmid":"27018657","pmcid":null,"openalex_id":"W2190085061","pdf_url":"https://arxiv.org/pdf/1512.02933","abstract":"Hydrogen compounds are peculiar as the quantum nature of the proton can crucially affect their structural and physical properties. A remarkable example are the high-pressure phases of H$_2$O, where quantum proton fluctuations favor the symmetrization of the H bond and lower by 30 GPa the boundary between the asymmetric structure and the symmetric one. Here we show that an analogous quantum symmetrization occurs in the recently discovered sulfur hydride superconductor with the record superconducting critical temperature $T_c=203$ K at 155 GPa. In this system, according to classical theory, superconductivity occurs via formation of a structure of stoichiometry H$_3$S with S atoms arranged on a body-centered-cubic (bcc) lattice. For $P \\gtrsim 175$ GPa, the H atoms are predicted to sit midway between two S atoms, in a structure with $Im\\bar3m$ symmetry. At lower pressures the H atoms move to an off-center position forming a short H$-$S covalent bond and a longer H$\\cdots$S hydrogen bond, in a structure with $R3m$ symmetry. X-ray diffraction experiments confirmed the H$_3$S stoichiometry and the S lattice sites, but were unable to discriminate between the two phases. Our present ab initio density-functional theory (DFT) calculations show that the quantum nuclear motion lowers the symmetrization pressure by 72 GPa. Consequently, we predict that the $Im\\bar3m$ phase is stable over the whole pressure range within which a high $T_c$ was measured. The observed pressure-dependence of $T_c$ is closely reproduced in our calculations for the $Im\\bar3m$ phase, but not for the $R3m$ phase. Thus, the quantum nature of the proton completely rules the superconducting phase diagram of H$_3$S.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:2106.09879","kind":"article","title":"Design Principles for High Temperature Superconductors with Hydrogen-based Alloy Backbone at Moderate Pressure","authors":["Zihan Zhang","Tian Cui","Michael J. Hutcheon","Alice M. Shipley","Hao Song","Mingyang Du","Vladimir Z. Kresin","Defang Duan","Chris J. Pickard","Yansun Yao"],"author_count":10,"year":2021,"published":"2021-06-18","venue":"Physical Review Letters","cited_by":255,"doi":"10.1103/physrevlett.128.047001","arxiv_id":"2106.09879","nct_id":null,"source_url":"https://arxiv.org/abs/2106.09879","archive_url":"https://space-kitty.com/papers/arxiv:2106.09879","updated":"2021-06-27","pmid":"35148145","pmcid":null,"openalex_id":"W3174887187","pdf_url":"https://arxiv.org/pdf/2106.09879","abstract":"Hydrogen-based superconductors provide a route to the long-sought goal of room-temperature superconductivity, but the high pressures required to metallize these materials limit their immediate application. For example, carbonaceous sulfur hydride, the first room-temperature superconductor, can reach a critical temperature (Tc) of 288 K only at the extreme pressure of 267 GPa. The next recognized challenge is the realization of room-temperature superconductivity at significantly lower pressures. Here, we propose a strategy for the rational design of high-temperature superconductors at low pressures by alloying small-radius elements and hydrogen to form ternary hydride superconductors with alloy backbones. We identify a hitherto unknown fluorite-type backbone in compositions of the form AXH8, which exhibit high temperature superconductivity at moderate pressures. The Fm-3m phase of LaBeH8, with a fluorite-type H-Be alloy backbone, is predicted to be metastable and superconducting with a Tc ~ 191 K at 50 GPa; a substantially lower pressure than that required by the geometrically similar clathrate hydride LaH10 (170 GPa). Our approach paves the way for finding high-Tc ternary hydride superconductors at conditions close to ambient pressures.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["cond-mat.supr-con"],"details":null,"provenance":"arxiv+openalex","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1910.00385","kind":"review","title":"Superconducting Hydrides Under Pressure","authors":["Chris J. Pickard","Ion Errea","Mikhail I. Eremets"],"author_count":3,"year":2019,"published":"2019-09-26","venue":"Annual Review of Condensed Matter Physics","cited_by":280,"doi":"10.1146/annurev-conmatphys-031218-013413","arxiv_id":"1910.00385","nct_id":null,"source_url":"https://doi.org/10.1146/annurev-conmatphys-031218-013413","archive_url":"https://space-kitty.com/papers/arxiv:1910.00385","updated":"2019-10-01","pmid":null,"pmcid":null,"openalex_id":"W2977210627","pdf_url":"https://www.annualreviews.org/doi/pdf/10.1146/annurev-conmatphys-031218-013413","abstract":"The measurement of superconductivity at above 200K in compressed samples of hydrogen sulfide and lanthanum hydride at 250K is reinvigorating the search for conventional high temperature superconductors. At the same time it exposes a fascinating interplay between theory, computation and experiment. Conventional superconductivity is well understood, and theoretical tools are available for accurate predictions of the superconducting critical temperature. These predictions depend on knowing the microscopic structure of the material under consideration, and can now be provided through computational first principles structure predictions. The experiments at the megabar pressures required are extremely challenging, but for some groups at least, permit the experimental exploration of materials space. We discuss the prospects for the search for new superconductors, ideally at lower pressures.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:1904.06643","kind":"article","title":"Superconducting Praseodymium Superhydrides","authors":["Di Zhou","Dmitrii Semenok","Defang Duan","Hui Xie","Xiaoli Huang","Wuhao Chen","Xin Li","Bingbing Liu","Artem R. Oganov","Tian Cui"],"author_count":10,"year":2019,"published":"2019-04-14","venue":"Science Advances, 2020","cited_by":158,"doi":"10.1126/sciadv.aax6849","arxiv_id":"1904.06643","nct_id":null,"source_url":"https://arxiv.org/abs/1904.06643","archive_url":"https://space-kitty.com/papers/arxiv:1904.06643","updated":"2019-12-04","pmid":null,"pmcid":null,"openalex_id":"W3007707307","pdf_url":"https://arxiv.org/pdf/1904.06643","abstract":"Superhydrides have complex hydrogenic sublattices and are important prototypes for studying metallic hydrogen and high-temperature superconductors. Encouraged by the results on LaH10, in consideration of the differences between La and Pr, Pr-H system is especially worth studying because of the magnetism and valence-band f-electrons in element Pr. Here we successfully synthesized praseodymium superhydrides (PrH9) in laser-heated diamond anvil cells. Synchrotron X-ray diffraction (XRD) analysis demonstrated the presence of previously predicted F43m-PrH9 and unexpected P63/mmc-PrH9 phases. Moreover, Fm3m-PrH3, P4/nmm-PrH(3-δ) and Fm3m-PrH(1+x) were found below 52 GPa. F43m-PrH9 and P63/mmc-PrH9 were stable above 100 GPa in experiment. Experimental studies of electrical resistance in the PrH9 sample showed the emergence of superconducting transition (Tc) below 9K and a dependent Tc on applied magnetic field. Theoretical calculations indicate that magnetic order and electron-phonon interaction coexist in a very close range of pressures in the PrH9 sample which may contribute to its low superconducting temperature Tc. Our results highlight the intimate connections among hydrogenic sublattices, density of states, magnetism and superconductivity in Pr-based superhydrides.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":false,"retracted":false,"peer_reviewed":null,"categories":["cond-mat.mtrl-sci","cond-mat.supr-con"],"details":null,"provenance":"arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"arxiv:2102.11227","kind":"article","title":"La BH 8 : Towards high- T c low-pressure superconductivity in ternary superhydrides","authors":["Simone Di Cataldo","Christoph Heil","Wolfgang von der Linden","Lilia Boeri"],"author_count":4,"year":2021,"published":"2021-07-29","venue":"Physical review. B./Physical review. B","cited_by":205,"doi":"10.1103/physrevb.104.l020511","arxiv_id":"2102.11227","nct_id":null,"source_url":"https://doi.org/10.1103/physrevb.104.l020511","archive_url":"https://space-kitty.com/papers/arxiv:2102.11227","updated":"2021-02-24","pmid":null,"pmcid":null,"openalex_id":"W3184031106","pdf_url":"https://arxiv.org/pdf/2102.11227","abstract":"In the last five years a large number of new high-temperature superconductors have been predicted and experimentally discovered among hydrogen-rich crystals, at pressures which are way too high to meet any practical application. In this work, we report the computational prediction of a hydride superconductor, LaBH$_{8}$, with a T$_{c}$ of 126 K at a pressure of 50 GPa, thermodynamically stable above 100 GPa, and dynamically stable down to 40 GPa, an unprecedentedly low pressure for high-T$_{c}$ hydrides. LaBH$_{8}$ can be seen as a ternary sodalite-like hydride, in which a metallic hydrogen sublattice is stabilized by the chemical pressure exerted by the guest elements. The combination of two elements with different atomic sizes in LaBH$_{8}$ realizes a more efficient packing of atoms than in binary sodalite hydrides. A suitable choice of elements may be exploited to further reduce the stabilization pressure to ambient conditions.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."},{"id":"openalex:W3099989971","kind":"article","title":"Superconducting Hydrides Under Pressure","authors":["Chris J. Pickard","Ion Errea","Eremets, M."],"author_count":3,"year":2020,"published":"2020-01-01","venue":"MPG.PuRe (Max Planck Society)","cited_by":218,"doi":null,"arxiv_id":null,"nct_id":null,"source_url":"http://hdl.handle.net/21.11116/0000-0007-4AC6-7","archive_url":"https://space-kitty.com/papers/openalex:W3099989971","updated":null,"pmid":null,"pmcid":null,"openalex_id":"W3099989971","pdf_url":null,"abstract":null,"abstract_license":null,"license":null,"is_open_access":false,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex","attribution":"Metadata and citation counts: OpenAlex (CC0)."},{"id":"arxiv:1501.00196","kind":"article","title":"What superconducts in sulfur hydrides under pressure and why","authors":["Noam Bernstein","C. Stephen Hellberg","M. D. Johannes","I. I. Mazin","Michael J. Mehl"],"author_count":5,"year":2015,"published":"2015-02-27","venue":"Physical Review B","cited_by":247,"doi":"10.1103/physrevb.91.060511","arxiv_id":"1501.00196","nct_id":null,"source_url":"https://doi.org/10.1103/physrevb.91.060511","archive_url":"https://space-kitty.com/papers/arxiv:1501.00196","updated":"2014-12-31","pmid":null,"pmcid":null,"openalex_id":"W1969463549","pdf_url":"https://arxiv.org/pdf/1501.00196","abstract":"The recent discovery of superconductivity at 190~K in highly compressed H$_{2}$S is spectacular not only because it sets a record high critical temperature, but because it does so in a material that appears to be, and we argue here that it is, a conventional strong-coupling BCS superconductor. Intriguingly, superconductivity in the observed pressure and temperature range was predicted theoretically in a similar compound H$_{3}$S. Several important questions about this remarkable result, however, are left unanswered: (1) Does the stoichiometry of the superconducting compound differ from the nominal composition, and could it be the predicted H$_{3}$S compound? (2) Is the physical origin of the anomalously high critical temperature related only to the high H phonon frequencies, or does strong electron-ion coupling play a role? We show that at experimentally relevant pressures H$_2$S is unstable, decomposing into H$_3$S and S, and that H$_3$S has a record high $T_c$ due to its covalent bonds driven metallic. The main reason for this extraordinarily high $T_c$ in H$_3$S as compared with MgB$_2$, another compound with a similar superconductivity mechanism, is the high vibrational frequency of the much lighter H atoms.","abstract_license":"CC0-1.0 (arXiv descriptive metadata)","license":null,"is_open_access":true,"retracted":false,"peer_reviewed":null,"categories":["High-pressure geophysics and materials"],"details":null,"provenance":"openalex+arxiv","attribution":"Abstract: arXiv descriptive metadata (CC0). Thank you to arXiv for use of its open access interoperability. This service was not reviewed or approved by, nor does it necessarily express or reflect the policies or opinions of, arXiv."}],"next":"https://space-kitty.com/api/v1/topics/hydride-superconductors/papers?sort=top&limit=25&offset=25"}