Interplay between magnetic gap and quasiparticle lifetime in topological insulator ferromagnet/f-wave superconductor junctions  

作　　者：Hong Li Xinjian Yang 

机构地区：[1]College of Science,China University of Petroleum,Qingdao 266580,China

出　　处：《Communications in Theoretical Physics》2024年第7期156-164,共9页理论物理通讯（英文版）

摘　　要：Using the modified Blonder-Tinkham-Klapwijk(BTK)theory,the interplay between the lifetime of quasi particles and the magnetic gap in a topological insulator-based ferromagnet/fwave superconductor(TI-based FM/f-wave SC)tunnel structure is theoretically studied.Two symmetries of f_(1) and f_(2) waves are considered for superconducting pairing states.The results indicate that reducing the finite quasi-particle lifetime will induce a transformation of energy-gap peaks into a zero-bias peak in tunneling conductance spectrum,as well as a transformation of energy-gap dips into a zero-bias dip in shot noise spectrum,ultimately resulting in the smoothing of the zero-bias conductance peak and the zero-bias shot noise dip.An increase in magnetic gap will suppress the tunnel conductance and shot noise when the conventional Andreev retroreflection dominates,but will enhance them when the specular Andreev reflection is dominant.Both specular Andreev reflection and conventional Andreev retro-reflection will be enhanced as the quasi-particle lifetime increases.When Fermi energy equals the magnetic gap,shot noise and tunneling conductance vanish across all energy ranges.These findings not only contribute to a better understanding of specular Andreev reflection in the FM/f-wave SC junction based on TIs but also provide insights for experimentally determining the f-wave pairing symmetry.

关 键 词：TI-based FM/f-wave SC junction magnetic gap finite-quasi-particles lifetime Andreev retro-reflection specular Andreev reflection 

分 类 号：O469[理学—凝聚态物理]