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Robust topological insulator surface state in MBE grown (Bi_{1-x}Sb_x)_2Se_3

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 نشر من قبل Cheong-Wei Chong
 تاريخ النشر 2016
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Y. Hung Liu




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(Bi1-xSbx)2Se3 thin films have been prepared using molecular beam epitaxy (MBE). We demonstrate the angle-resolved photoemission spectroscopy (ARPES) and transport evidence for the existence of strong and robust topological surface states in this ternary system. Large tunability in transport properties by varying the Sb doping level has also been observed, where insulating phase could be achieved at x=0.5. Our results reveal the potential of this system for the study of tunable topological insulator and metal-insulator transition based device physics.



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