Probing the breakdown of topological protection: Filling-factor-dependent evolution of robust quantum Hall incompressible phases

Toru Tomimatsu, Katsushi Hashimoto, S. Taninaka, S. Nomura, Y. Hirayama

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

The integer quantum Hall (QH) effects characterized by topologically quantized and nondissipative transport are caused by an electrically insulating incompressible phase that prevents backscattering between chiral metallic channels. We probed the incompressible area susceptible to the breakdown of topological protection using a scanning-gate technique incorporating nonequilibrium transport. The obtained pattern revealed the filling-factor- (ν-) dependent evolution of the microscopic incompressible structures located along the edge and in the bulk region. We found that these specific structures, respectively, attributed to the incompressible edge strip and bulk localization, show good agreement in terms of ν-dependent evolution with a calculation of the equilibrium QH incompressible phases, indicating the robustness of the QH incompressible phases under the nonequilibrium condition. Further, we found that the ν dependency of the incompressible patterns is, in turn, destroyed by a large imposed current during the deep QH effect breakdown. These results demonstrate the ability of our method to image the microscopic transport properties of a topological two-dimensional system.

Original languageEnglish
Article number013128
JournalPhysical Review Research
Volume2
Issue number1
DOIs
Publication statusPublished - 2020 Feb

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'Probing the breakdown of topological protection: Filling-factor-dependent evolution of robust quantum Hall incompressible phases'. Together they form a unique fingerprint.

Cite this