Optimal alloying in hydrides: Reaching room-temperature superconductivity in LaH10
Optimal alloying in hydrides: Reaching room-temperature superconductivity in LaH10
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DOI：
10.1103/physrevb.105.174516
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发表时间：
2022-05
影响因子：
3.7
通讯作者：
Tianchun Wang;J. A. Flores-Livas;T. Nomoto;Yanming Ma;T. Koretsune;R. Arita
中科院分区：
文献类型：
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作者：
Tianchun Wang;J. A. Flores-Livas;T. Nomoto;Yanming Ma;T. Koretsune;R. Arita
掺杂是优化超导体最有前途的途径之一，例如具有破纪录临界温度的高压常规超导体。在这项工作中，我们进行了广泛的搜索替代掺杂剂，寻找元素，提高其电子结构。总共有70种元素在高压下以12.5%的掺杂比被研究作为可能的La-位点的替代。为了加速三元相的筛选，我们的扫描化学空间的协议是1）被约束到氢原子的高度对称图案，2）关注具有镧原子的紧凑基础的相（最小化焓）和3）选择保持费米能级周围的货车霍韦奇异性的候选掺杂剂。我们发现Ca是最好的候选掺杂剂，它移动了货车霍韦奇点，并增加了费米能级的电子态密度。采用谐波声子能级计算和第一性原理计算，Ca掺杂比掺杂提高了15%。这为通过掺杂实现加压超导提供了一条很有前途的途径。
Doping represents one of the most promising avenues for optimizing superconductors, such as high-pressure conventional superconductors with record-breaking critical temperatures. In this work, we perform an extensive search for substitutional dopants in, looking for elements that enhance its electronic structure. In total, 70 elements were investigated as possible substitutions of La-sites at doping ratio of 12.5% under high pressure. To accelerate the screening of the ternary phases, our protocol to scan the chemical space is 1) to be constrained to highly symmetric patterns of hydrogen atoms, 2) focusing on phases with compact basis of lanthanum atoms (minimize enthalpy) and 3) to choose candidate dopants that preserve the van Hove singularity around the Fermi level. We found Ca as the best candidate dopants, which shift the van Hove singularity and increase the electronic DOS at the Fermi level. By using harmonic-level phonon calculations and performing first-principles calculation of, Ca-dopedshowswhich is 15% higher than the one of. It provides a promising route to reach room-temperature superconductivity in pressurized hydrides by doping.