Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ, Brazil.
Phys Rev Lett. 2010 Sep 17;105(12):126401. doi: 10.1103/PhysRevLett.105.126401. Epub 2010 Sep 13.
We report a combined pressure-doping study in the nearly two-dimensional heavy fermion superconductor CeCoIn5 as its superconducting phase is driven to the normal state by Sn doping and/or applied pressure. Temperature-pressure-dependent electrical resistivity measurements were performed at the vicinity of a superconducting quantum critical point where Tc→0. A universal plot of the concentration- and pressure-dependent phase diagram suggests that for the concentrations studied a single mechanism is responsible for reducing Tc and bringing the system to the superconducting quantum critical point. A two-band model with hybridization controlled by pressure and doping provides a consistent description of the phase diagram and the suppression of the d-wave superconductivity in this material.
我们报告了在近二维重费米子超导体 CeCoIn5 中的压力掺杂联合研究,因为其超导相通过 Sn 掺杂和/或施加压力被驱动到正常状态。在接近超导量子临界点的地方进行了温度-压力依赖的电阻率测量,其中 Tc→0。浓度和压力依赖的相图的通用图表明,在所研究的浓度下,单一机制负责降低 Tc 并将系统带到超导量子临界点。具有由压力和掺杂控制的杂化的双带模型为相图和该材料中 d 波超导性的抑制提供了一致的描述。