Uniaxial Strain Orientation Dependence of Superconducting Transition Temperature (Tc) and Critical Superconducting Pressure (Pc) in β-(BDA-TTP)2I3

Dependence of the superconducting transition temperature (Tc) and critial superconducting pressure (Pc) of the pressure-induced superconductor β-(BDA-TTP)2I3 [BDA-TTP = 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene] on the orientation of uniaxial strain has been investigated. On the basis of the overlap between the upper and lower bands in the energy dispersion curve, the pressure orientation is thought to change the half-filled band to the quarter-filled one. The observed variations in Tc and Pc are explained by considering the degree of application of the pressure and the degree of contribution of the effective electronic correlation at uniaxial strains with different orientations parallel to the conducting donor layer.

本研究针对压力诱导超导体β-(BDA-TTP)₂I₃ [BDA-TTP=2,5-双(1,3-二噻烷-2-亚基)-1,3,4,6-四硫杂戊搭烯]的超导转变温度（Tc）与临界超导压力（Pc）随单轴应变取向的依赖关系展开了探究。基于能量色散曲线中上下能带的重叠特性，研究认为单轴应变的取向可将半满能带转变为四分之一满能带。通过考量平行于导电给体层的不同取向单轴应变下的压力施加程度与有效电子关联的贡献程度，可对实验观测到的Tc与Pc变化作出合理解释。