Landau Quantization of Massless Dirac Fermions in Topological Insulator

Understand

The recent theoretical prediction and experimental realization of topological insulators (TI) has generated intense interest in this new state of quantum matter.

• The surface states of a three-dimensional (3D) TI such as Bi_2Te_3, Bi_2Se_3 and Sb_2Te_3 consist of a single massless Dirac cones.
• Crossing of the two surface state branches with opposite spins in the materials is fully protected by the time reversal (TR) symmetry at the Dirac points, which cannot be destroyed by any TR invariant perturbation.
• Recent advances in thin-film growth have permitted this unique two-dimensional electron system (2DES) to be probed by scanning tunneling microscopy (STM) and spectroscopy (STS).