Helical edge and surface states in HgTe quantum wells and bulk insulators

Abstract

The quantum spin Hall (QSH) effect is the property of a new state of matter which preserves time-reversal, has an energy gap in the bulk, but has topologically robust gapless states at the edge. Recently, it has been shown that HgTe quantum wells realize this novel effect. In this work, we start from realistic tight-binding models and demonstrate the existence of the helical edge states in HgTe quantum wells and calculate their physical properties. We also show that 3d HgTe is a topological insulator under uniaxial strain, and show that the surface states are described by single-component massless relativistic Dirac fermions in 2+1 dimensions. Experimental predictions are made based on the quantitative results obtained from realistic calculations.

5 pages

References in corpus (6)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Dissipationless Quantum Spin Current at Room Temperature
• The Helical Liquid and the Edge of Quantum Spin Hall Systems
• SU(2) Non-Abelian Holonomy and Dissipationless Spin Current in Semiconductors

Cited by in corpus (6)

• Classification of topological insulators and superconductors in three spatial dimensions
• Topological Field Theory of Time-Reversal Invariant Insulators
• Finite size effects of helical edge states in HgTe/CdTe quantum wells
• Electronic Structures and Surface States of Topological Insulator Bi${}_{1-x}$Sb${}_x$
• Spin Charge Separation in the Quantum Spin Hall State
• Properties of A Class of Topological Phase Transition