Tunneling conductance in ferromagnet/superconductor junctions with time-reversal symmetry breaking  

作　　者：Li Hong Xin Jian Yang 

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

出　　处：《Communications in Theoretical Physics》2025年第4期151-158,共8页理论物理通讯(英文版)

基　　金：supported by the Fundamental Research Funds for the Central Universities(Grant Nos.23CX03016A and 24CX030009A)。

摘　　要：The tunneling conductance of two kinds of tunnel junctions with time-reversal symmetry breaking,normal metal/insulator/ferromagnetic metal/dx_(2-y2)+is-wave superconductor(NM/I/FM/dx_(2-y2)+is-wave SC)and NM/I/FM/dx_(2-y2)+idxy-wave SC,is calculated using the extended Blonder-Tinkham-Klapwijk theoretical method.The ratio of the subdominant s-wave and dxy-wave components to the dominant dx_(2-y2)-wave component is expressed byΔ_(s)/Δ_(D)andΔ_(d)/Δ_(D),respectively.Results show that for NM/I/FM/dx_(2-y2)+is-wave SC tunnel junctions,the splitting of the zero-bias conductance peak(ZBCP)is obtained and the splitting peaks appear at eV/Δ_(0)=±Δ_(s)/Δ_(D)with eV the applied bias voltage andΔ_(0)the zero temperature energy gap of SC.For NM/I/FM/dx_(2-y2)+idxy-wave SC tunnel junctions,there are also conductance peaks at eV/Δ_(0)=±Δ_(d)/Δ_(D)but the ZBCP does not split.For the two types of tunnel junctions,the completely reversed tunnel conductance spectrum indicates that when the exchange energy in FM is increased to a certain value,the proximity effect transforms the tunnel junctions from the'0 state'to the'πstate'.The shortening of the transport quasiparticle lifetime can weaken the proximity effect to smooth out the dips and peaks in the tunnel spectrum.This is considered a possible reason that the ZBCP splitting was not observed in some previous experiments.It is expected that these analysis results can serve as a guide for future experiments and the relevant conclusions can be confirmed.

关 键 词：dx^(2)+y^(2)+is-wave dx^(2)+y^(2)+id_(ay)-wave time-reversal symmetry breaking quasiparticle lifetime effect proximity effect 

分 类 号：O469[理学—凝聚态物理]