Unconventional Topological Phase Transition in Two-Dimensional Systems with Space-Time Inversion Symmetry

Cited 6 time in webofscience Cited 0 time in scopus
172 Viewed 37 Downloaded
Title
Unconventional Topological Phase Transition in Two-Dimensional Systems with Space-Time Inversion Symmetry
Author(s)
Junyeong Ahn; Bohm-Jung Yang
Publication Date
2017-04
Journal
PHYSICAL REVIEW LETTERS, v.118, no.15, pp.156401 -
Publisher
AMER PHYSICAL SOC
Abstract
We study a topological phase transition between a normal insulator and a quantum spin Hall insulator in two-dimensional (2D) systems with time-reversal and twofold rotation symmetries. Contrary to the case of ordinary time-reversal invariant systems, where a direct transition between two insulators is generally predicted, we find that the topological phase transition in systems with an additional twofold rotation symmetry is mediated by an emergent stable 2D Weyl semimetal phase between two insulators. Here the central role is played by the so-called space-time inversion symmetry, the combination of time-reversal and twofold rotation symmetries, which guarantees the quantization of the Berry phase around a 2D Weyl point even in the presence of strong spin-orbit coupling. Pair creation and pair annihilation of Weyl points accompanying partner exchange between different pairs induces a jump of a 2D Z2 topological invariant leading to a topological phase transition. According to our theory, the topological phase transition in HgTe/CdTe quantum well structure is mediated by a stable 2D Weyl semimetal phase because the quantum well, lacking inversion symmetry intrinsically, has twofold rotation about the growth direction. Namely, the HgTe/CdTe quantum well can show 2D Weyl semimetallic behavior within a small but finite interval in the thickness of HgTe layers between a normal insulator and a quantum spin Hall insulator. We also propose that few-layer black phosphorus under perpendicular electric field is another candidate system to observe the unconventional topological phase transition mechanism accompanied by the emerging 2D Weyl semimetal phase protected by space-time inversion symmetry. © 2017 American Physical Society
URI
https://pr.ibs.re.kr/handle/8788114/3590
ISSN
0031-9007
Appears in Collections:
Center for Correlated Electron Systems(강상관계 물질 연구단) > Journal Papers (저널논문)
Files in This Item:
Unconventional Topological Phase Transition in Two-Dimensional Systems with Space-Time Inversion Symmetry_양범정.pdfDownload

qrcode

  • facebook

    twitter

  • Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
해당 아이템을 이메일로 공유하기 원하시면 인증을 거치시기 바랍니다.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse