APS Logo

Observation of excited state fractionally quantized Hall effects in the current biased GaAs/AlGaAs two dimensional electron system

ORAL

Abstract

A millikelvin magneto-transport study of the high mobility GaAs/AlGaAs two dimensional electron system, under a current bias, IDC, demonstrates that all observable canonical FQHE at ∣IDC∣ = 0 between 2 ≥ ν ≥ 1 undergo bimodal linear splitting in the resistance minima vs. IDC for ∣IDC∣ > 0, yielding diamond-like transport characteristics in the IDC vs. B color plots of the resistance, as the equilibrium FQHE at filling factor ν ~ p/q, are replaced with increasing IDC , by (hybrid) non-equilibrium excited-state fractionally quantized Hall effects at the intersection of the resistance minima branches originating from different equilibrium FQHE. Similar diamond-like transport characteristics have also been observed for FQHE with ν ≤ 1. A tunneling model, which recalls some aspects of the modeling for the diamond-like patterns observed in electron charging experiments on small quantum dots, is suggested here to help understand the observed bimodal splitting of the FQHE resistance minima and the diamond-like transport characteristics in the IDC vs. B color plots of the resistance.The results suggest an interesting new experimental method to investigate and gain further insight into FQHE.

Publication: Wijewardena, U.K., Mani, R.G., Kriisa, A. et al. Non-equilibrium excited-state fractionally quantized Hall effects observed via current bias spectroscopy. Commun Phys 7, 267 (2024).

Presenters

  • Ramesh Mani

    Georgia State University

Authors

  • Ramesh Mani

    Georgia State University

  • U K Wijewardena

    Georgia State University

  • Annika Kriisa

    Georgia State University

  • Christian Reichl

    ETH Zurich, ETH-Zurich, Department of Physics, ETH Zurich

  • Werner Wegscheider

    ETH Zurich, ETH-Zurich, Department of Physics, ETH Zurich