Quantum criticality and superconducting pairing in Ce 1-x Yb x CoIn 5 alloys
Quantum criticality and superconducting pairing in Ce 1-x Yb x CoIn 5 alloys
复制标题
Ce 1-x Yb x CoIn 5 合金中的量子临界性和超导配对
DOI：
10.1088/1742-6596/592/1/012078
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Almasan, C C
中科院分区：
文献类型：
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作者：
Singh, Y P;Haney, D J;Lum, I K;White, B D;Maple, M B;Dzero, M;Almasan, C C
Ce 1-xYbxCoIn 5单晶合金在磁场和压力下的电荷输运测量结果表明：（i）相对小的Yb掺杂抑制了场诱导量子临界点，当Yb掺杂x> 0.0 7时，场诱导量子临界点完全被抑制;（ii）超导转变温度（Tc）和近藤晶格相干温度（Tcoh）随x降低，但在较宽的Yb掺杂浓度范围内，Tc和Tcoh仍然是有限的;（iii）Tc和Tcoh均随压力的增加而增加;（iv）电阻率有两种贡献，表现出不同的温度和压力依赖性，这意味着重准粒子和轻准粒子都对非弹性散射有贡献.我们还分析了压力的依赖性的复合配对理论内的Tcoh和Tc。在纯静态极限下，我们发现复合配对机制必然导致Tcoh和Tc随压力的相反行为：如果Tcoh随压力增大，Tc必然随压力减小，反之亦然.
Charge transport measurements under magnetic field and pressure on Ce 1-x Yb x CoIn 5 single crystalline alloys revealed that:(i) relatively small Yb substitution suppresses the field induced quantum critical point, with a complete suppression for Yb doping x> 0.07;(ii) the superconducting transition temperature (T c) and Kondo lattice coherence temperature (T coh) decrease with x, yet they remain finite over the wide range of Yb concentrations;(iii) both T c and T coh increase with pressure;(iv) there are two contributions to resistivity, which show different temperature and pressure dependences, implying that both heavy and light quasiparticles contribute to inelastic scattering. We also analyzed the pressure dependence of both T coh and T c within the composite pairing theory. In the purely static limit, we find that the composite pairing mechanism necessarily causes opposite behaviors of T coh and T c with pressure: if Tcoh grows with pressure, T c must decrease with pressure and vice versa.