Massive Dirac fermion on the surface of a magnetically doped topological insulator.
نویسندگان
چکیده
In addition to a bulk energy gap, topological insulators accommodate a conducting, linearly dispersed Dirac surface state. This state is predicted to become massive if time reversal symmetry is broken, and to become insulating if the Fermi energy is positioned inside both the surface and bulk gaps. We introduced magnetic dopants into the three-dimensional topological insulator dibismuth triselenide (Bi2Se3) to break the time reversal symmetry and further position the Fermi energy inside the gaps by simultaneous magnetic and charge doping. The resulting insulating massive Dirac fermion state, which we observed by angle-resolved photoemission, paves the way for studying a range of topological phenomena relevant to both condensed matter and particle physics.
منابع مشابه
Massive Dirac Fermion Observed in Lanthanide-Doped Topological Insulator Thin Films
The breaking of time reversal symmetry (TRS) in three-dimensional (3D) topological insulators (TIs), and thus the opening of a 'Dirac-mass gap' in the linearly dispersed Dirac surface state, is a prerequisite for unlocking exotic physical states. Introducing ferromagnetic long-range order by transition metal doping has been shown to break TRS. Here, we present the study of lanthanide (Ln) doped...
متن کاملCompetition between weak localization and antilocalization in topological surface states.
A magnetoconductivity formula is presented for the surface states of a magnetically doped topological insulator. It reveals a competing effect of weak localization and weak antilocalization in quantum transport when an energy gap is opened at the Dirac point by magnetic doping. It is found that, while random magnetic scattering always drives the system from the symplectic to the unitary class, ...
متن کاملMassive and massless Dirac fermions in Pb1−xSnxTe topological crystalline insulator probed by magneto-optical absorption
Dirac fermions in condensed matter physics hold great promise for novel fundamental physics, quantum devices and data storage applications. IV-VI semiconductors, in the inverted regime, have been recently shown to exhibit massless topological surface Dirac fermions protected by crystalline symmetry, as well as massive bulk Dirac fermions. Under a strong magnetic field (B), both surface and bulk...
متن کاملDual Dirac Liquid on the Surface of the Electron Topological Insulator
The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. We discuss a non-Fermi liquid gapless metallic surface state of the topological band insulator. It has an odd number of gapless Dirac fermions coupled to a noncompact Uð1Þ gauge field. This can be viewed as a vortex dual to the conventional Dirac fermion surface state. This sur...
متن کاملMagnetism-induced massive Dirac spectra and topological defects in the surface state of Cr-doped Bi2Se3-bilayer topological insulators
1 Department of Physics, California Institute of Technology, Pasadena, CA 91125, USA 2 Institute of Quantum Matter and Information, California Institute of Technology, Pasadena, CA 91125, USA 3 Department of Electrical Engineering, University of California, Los Angeles, CA 90095, USA 4 Kavli Nanoscience Institute, California Institute of Technology, Pasadena, CA 91125, USA * E-mail: ncyeh@calte...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Science
دوره 329 5992 شماره
صفحات -
تاریخ انتشار 2010