Characterization of Fermi surface of the BaSn3 superconductor(Tc~ 4.4K)by de Haas–van Alphen(dHvA)effect measurement reveals its non-trivial topological properties.Analysis of non-zero Berry phase is supported by the...Characterization of Fermi surface of the BaSn3 superconductor(Tc~ 4.4K)by de Haas–van Alphen(dHvA)effect measurement reveals its non-trivial topological properties.Analysis of non-zero Berry phase is supported by the ab initio calculations,which reveals a type-II Dirac point setting and tilting along the high symmetric K–H line of the Brillouin zone,about 0.13 eV above the Fermi level,and other two type-I Dirac points on the high symmetric Г–A direction,but slightly far below the Fermi level.The results demonstrate BaSn3 as an excellent example hosting multiple Dirac fermions and an outstanding platform for studying the interplay between nontrivial topological states and superconductivity.展开更多
Signatures of topological superconductivity(TSC)in superconducting materials with topological nontrivial states prompt intensive researches recently.Utilizing high-resolution angle-resolved photoemission spectroscopy ...Signatures of topological superconductivity(TSC)in superconducting materials with topological nontrivial states prompt intensive researches recently.Utilizing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations,we demonstrate multiple Dirac fermions and surface states in superconductor BaSn_(3) with a critical transition temperature of about 4.4 K.We predict and then unveil the existence of two pairs of type-Ⅰtopological Dirac fermions residing on the rotational axis.Type-ⅡDirac fermions protected by screw axis are confirmed in the same compound.Further calculation for the spin helical texture of the observed surface states originating from the Dirac fermions gives an opportunity for realization of TSC in one single material.Hosting multiple Dirac fermions and topological surface states,the intrinsic superconductor BaSn_(3) is expected to be a new platform for further investigation of topological quantum materials as well as TSC.展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.11874264)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA18000000)+3 种基金the Starting Grant of Shanghai Tech University,the Shenzhen Peacock Team Plan(Grant No.KQTD20170809110344233)the Bureau of Industry and Information Technology of Shenzhen through the Graphene Manufacturing Innovation Center(Grant No.201901161514)the Key Scientific Research Projects of Higher Institutions in Henan Province(19A140018)Analytical Instrumentation Center,SPST,Shanghai Tech University(Grant No.SPST-AIC10112914).
文摘Characterization of Fermi surface of the BaSn3 superconductor(Tc~ 4.4K)by de Haas–van Alphen(dHvA)effect measurement reveals its non-trivial topological properties.Analysis of non-zero Berry phase is supported by the ab initio calculations,which reveals a type-II Dirac point setting and tilting along the high symmetric K–H line of the Brillouin zone,about 0.13 eV above the Fermi level,and other two type-I Dirac points on the high symmetric Г–A direction,but slightly far below the Fermi level.The results demonstrate BaSn3 as an excellent example hosting multiple Dirac fermions and an outstanding platform for studying the interplay between nontrivial topological states and superconductivity.
基金Supported by the National Key R&D Program of China (Grant No. 2016YFA0300204)the National Natural Science Foundation of China (Grant Nos. U2032208 and 11874264)+6 种基金the Natural Science Foundation of Shanghai (Grant No. 14ZR1447600)the starting grant of Shanghai Tech University and the Program for Professor of Special Appointment (Shanghai Eastern Scholar)supported by ME~2 project (Grant No. 11227902) from the National Natural Science Foundation of Chinasupported by the National Natural Science Foundation of China (Grant No. 11974395)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB33000000)the Center for Materials Genomethe support from Analytical Instrumentation Center,SPST,Shanghai Tech University (Grant No. SPST-AIC10112914)
文摘Signatures of topological superconductivity(TSC)in superconducting materials with topological nontrivial states prompt intensive researches recently.Utilizing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations,we demonstrate multiple Dirac fermions and surface states in superconductor BaSn_(3) with a critical transition temperature of about 4.4 K.We predict and then unveil the existence of two pairs of type-Ⅰtopological Dirac fermions residing on the rotational axis.Type-ⅡDirac fermions protected by screw axis are confirmed in the same compound.Further calculation for the spin helical texture of the observed surface states originating from the Dirac fermions gives an opportunity for realization of TSC in one single material.Hosting multiple Dirac fermions and topological surface states,the intrinsic superconductor BaSn_(3) is expected to be a new platform for further investigation of topological quantum materials as well as TSC.
