The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological states.ATi_(3)Bi_(5)present promising platforms for studyin...The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological states.ATi_(3)Bi_(5)present promising platforms for studying kagome superconductivity,band topology,and charge orders in parallel with AV3Sb5.In this work,we comprehensively analyze various properties of ATi_(3)Bi_(5)covering superconductivity under pressure and doping,band topology under pressure,thermal conductivity,heat capacity,electrical resistance,and spin Hall conductivity(SHC)using first-principles calculations.Calculated superconducting transition temperature(Tc)of CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)at ambient pressure are about 1.85 and 1.92 K.When subject to pressure,Tc of CsTi_(3)Bi_(5)exhibits a special valley and dome shape,which arises from quasi-two-dimensional compression to three-dimensional isotropic compression within the context of an overall decreasing trend.Furthermore,Tc of RbTi_(3)Bi_(5)can be effectively enhanced up to 3.09 K by tuning the kagome van Hove singularities(VHSs)and flat band through doping.Pressures can also induce abundant topological surface states at the Fermi energy(EF)and tune VHSs across EF.Additionally,our transport calculations are in excellent agreement with recent experiments,confirming the absence of charge density wave.Notably,SHC of CsTi_(3)Bi_(5)can reach up to 226h·(e·Ω·cm)^(-1)at EF.Our work provides a timely and detailed analysis of the rich physical properties for ATi_(3)Bi_(5),offering valuable insights for further experimental verifications and investigations in this field.展开更多
基金supported in part by the National Key R&D Program of China(Grant No.2018YFA0305800)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB28000000)+5 种基金the National Natural Science Foundation of China(Grant No.11834014)the Innovation Program for Quantum Science and Technology(No.2021ZD0301800)B.G.is supported in part by the National Natural Science Foundation of China(Grant No.12074378)the Chinese Academy of Sciences(Grant No.YSBR-030 and No.Y929013EA2)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB33000000)the Beijing Natural Science Foundation(Grant No.Z190011).
文摘The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological states.ATi_(3)Bi_(5)present promising platforms for studying kagome superconductivity,band topology,and charge orders in parallel with AV3Sb5.In this work,we comprehensively analyze various properties of ATi_(3)Bi_(5)covering superconductivity under pressure and doping,band topology under pressure,thermal conductivity,heat capacity,electrical resistance,and spin Hall conductivity(SHC)using first-principles calculations.Calculated superconducting transition temperature(Tc)of CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)at ambient pressure are about 1.85 and 1.92 K.When subject to pressure,Tc of CsTi_(3)Bi_(5)exhibits a special valley and dome shape,which arises from quasi-two-dimensional compression to three-dimensional isotropic compression within the context of an overall decreasing trend.Furthermore,Tc of RbTi_(3)Bi_(5)can be effectively enhanced up to 3.09 K by tuning the kagome van Hove singularities(VHSs)and flat band through doping.Pressures can also induce abundant topological surface states at the Fermi energy(EF)and tune VHSs across EF.Additionally,our transport calculations are in excellent agreement with recent experiments,confirming the absence of charge density wave.Notably,SHC of CsTi_(3)Bi_(5)can reach up to 226h·(e·Ω·cm)^(-1)at EF.Our work provides a timely and detailed analysis of the rich physical properties for ATi_(3)Bi_(5),offering valuable insights for further experimental verifications and investigations in this field.
