Superconductivity in La and Y hydrides: Remaining questions to experiment and theory

Struzhkin Viktor; Li Bing; Ji Cheng; Chen Xiao-Jia; Prakapenka Vitali; Greenberg Eran; Troyan Ivan; Gavriliuk Alexander; Mao Ho-kwang

doi:10.1063/1.5128736

Volume 5 Issue 2

Mar. 2020

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Article Navigation > Matter and Radiation at Extremes > 2020 > 5(2): 028201

Struzhkin Viktor, Li Bing, Ji Cheng, Chen Xiao-Jia, Prakapenka Vitali, Greenberg Eran, Troyan Ivan, Gavriliuk Alexander, Mao Ho-kwang. Superconductivity in La and Y hydrides: Remaining questions to experiment and theory[J]. Matter and Radiation at Extremes, 2020, 5(2): 028201. doi: 10.1063/1.5128736

Citation:

Struzhkin Viktor, Li Bing, Ji Cheng, Chen Xiao-Jia, Prakapenka Vitali, Greenberg Eran, Troyan Ivan, Gavriliuk Alexander, Mao Ho-kwang. Superconductivity in La and Y hydrides: Remaining questions to experiment and theory[J]. Matter and Radiation at Extremes, 2020, 5(2): 028201. doi: 10.1063/1.5128736

Citation:

Struzhkin Viktor, Li Bing, Ji Cheng, Chen Xiao-Jia, Prakapenka Vitali, Greenberg Eran, Troyan Ivan, Gavriliuk Alexander, Mao Ho-kwang. Superconductivity in La and Y hydrides: Remaining questions to experiment and theory[J]. Matter and Radiation at Extremes, 2020, 5(2): 028201. doi: 10.1063/1.5128736

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Superconductivity in La and Y hydrides: Remaining questions to experiment and theory

doi: 10.1063/1.5128736

1.
Center for High Pressure Science and Technology Advanced Research, Shanghai, China
2.
Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, USA
3.
Center for Advanced Radiation Sources, The University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA
4.
Federal Scientific Research Center Crystallography and Photonics, Russian Academy of Sciences, 59 Leninskii Pr-t, Moscow 119333, Russia
5.
Institute for Nuclear Research, Russian Academy of Sciences, Moscow, Troitsk 108840, Russia

More Information

Corresponding author: a)Author to whom correspondence should be addressed: viktor.struzhkin@hpstar.ac.cn
Received Date: 2019-09-29
Accepted Date: 2020-01-20

Available Online: 2020-03-01

Publish Date: 2020-03-15

Abstract

Abstract

Recent reports of the superconductivity in hydrides of two different families (covalent lattice, as in SH₃ and clathrate-type H-cages containing La and Y atoms, as in LaH₁₀ and YH₆) have revealed new families of high-T_c materials with T_c’s near room temperature values. These findings confirm earlier expectations that hydrides may have very high T_c’s due to the fact that light H atoms have very high vibrational frequencies, leading to high T_c values within the conventional Bardeen–Cooper–Schrieffer phonon mechanism of superconductivity. However, as is pointed out by Ashcroft, it is important to have the metallic hydrogen “alloyed” with the elements added to it. This concept of a metallic alloy containing a high concentration of metal-like hydrogen atoms has been instrumental in finding new high-T_c superhydrides. These new superhydride “room-temperature” superconductors are stabilized only at very high pressures above 100 GPa, making the experimental search for their superconducting properties very difficult. We will review the current experimental and theoretical results for LaH_10−x and YH_6−x superhydrides.

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References(51)

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