Enhancing superconductivity of Y5Rh6Sn18 by atomic disorder
Enhancing superconductivity of Y5Rh6Sn18 by atomic disorder
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通过原子无序增强Y5Rh6Sn18的超导性
DOI：
10.1103/physrevb.102.054514
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发表时间：
2020
影响因子：
3.7
通讯作者：
Maple, M. B.
中科院分区：
文献类型：
--
作者：
Ślebarski, A.;Fijałkowski, M.;Zajdel, P.;Maśka, M. M.;Deniszczyk, J.;Zubko, M.;Pavlosiuk, O.;Sasmal, K.;Maple, M. B.
本文研究了在填充的方钴矿类四方化合物中，Ca掺杂对超导转变温度的影响。实验证明，当Ca含量小于100%时，其掺杂合金在纳米尺度上是电子不均匀的，而当第二个3：4：13立方相的体积分数约为20%时，观察到更强的化学相不均匀性，我们将其解释为体样品内化学计量的波动。那么vscd的增强可以用最近的理论报告中提出的在存在双折射无序时增加平均场转变温度的机制来模拟。随着掺杂无序度的增加，样品的不均匀性增加，导致系统性的增加，而对于两相样品，临界温度迅速增加。基于在压力下进行的能带结构计算，我们演示了态密度的变化将如何影响。我们得到的Grüneisen参数较大的非均匀相相对于体相和属性的增强的高温相的更大的硬化。
We investigate the effect of enhancement of superconducting transition temperatureby nonmagnetic atom disorder in the filled skutterudite-related tetragonalcompound doped with Ca. We documented experimentally thatand its Ca-doped alloys are electronically inhomogeneous at the nanoscale, when Ca content is smaller thanin thesystem, while formuch stronger chemical phase inhomogeneity is observed with an about 20% volume fraction of the second 3:4:13 cubic phase, which we interpret as a fluctuation of stoichiometry within the bulk sample. Then the enhancement ofvscould be modeled by a mechanism proposed in recent theoretical reports for increasing the mean-field transition temperaturein the presence of nonmagnetic disorder. The increase in disorder with doping increases the sample inhomogeneity and causes a systematic increase in, while for two-phasesamples the critical temperaturerapidly increases. Based on band structure calculations performed under pressure, we demonstrate how the change in density of states would affectof. We obtained the Grüneisen parameterlarger for the inhomogeneous phase with respect toof the bulkphase and attribute the enhancement ofto larger stiffening of thehigh-temperaturephase.