Huge permittivity and premature metallicity in Bi2O2Se single crystals

作     者：ZhuoKai Xu JiaLu Wang Tao Wang WangHua Hu XiaoHui Yang Xiao Lin ZhuoKai Xu;JiaLu Wang;Tao Wang;WangHua Hu;XiaoHui Yang;Xiao Lin

作者机构：Deparment of PhysicsZhejiang UniversiyHangzhou 310027China Key Laboratory for Quantum Materials of Zhejiang ProvinceSchool of ScienceWestlake UniversityHangzhou 310024China Institute of Natural SciencesWestlake Instiute for Advanced StudyHangzhou 310024China 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2021年第64卷第6期

页      面：90-97页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.11904294) the Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ19A040005) the foundation of Westlake Multidisciplinary Research Initiative Center(MRIC)(Grant No.MRIC20200402) 

主　　题：next-generation semiconductor Bi_(2)O_(2)Se metal-insulator transition premature metallicity huge permittivity Mott’s criterion 

摘      要：Bi_(2)O_(2) Se is a promising material for next-generation semiconducting *** exhibits premature metallicity on the introduction of a tiny amount of electrons,the physics behind which remains *** we report on transport and dielectric measurements in Bi_(2)O_(2) Se single crystals at various carrier *** temperature-dependent resistivity(p)indicates a smooth evolution from the semiconducting to the metallic *** critical concentration for the metal-insulator transition(MIT)to occur is extraordinarily low(nc~10^(16) cm^(-3)).The relative permittivity of the insulating sample is huge(∈r≈155(10))and varies slowly with *** with the light effective mass,a long effective Bohr radius(a_(B)^(*)≈36(2)nm)is derived,which provides a reasonable interpretation of the metallic prematurity according to Mott’s criterion for *** high electron mobility(μ)at low temperatures may result from the screening of ionized scattering centers due to the huge∈*** findings shed light on the electron dynamics in two dimensional(2D)Bi_(2)O_(2) Se devices.