Fabry-Perot Interferometry with Fractional Charges

TL;DR

This study compares resistance oscillations in Fabry-Perot interferometers at fractional and integer quantum Hall states, revealing Coulomb dominance and effective tunneling charges, with distinct characteristic temperatures for FQH and IQH regimes.

Contribution

It demonstrates Coulomb dominance in FQH and IQH oscillations and identifies effective tunneling charges, highlighting differences in characteristic temperatures between fractional and integer regimes.

Findings

All oscillations are Coulomb dominated.

Effective tunneling charge is approximately e/3 for FQH and e for IQH.

Distinct characteristic temperatures for FQH and IQH oscillations.

Abstract

Resistance oscillations in electronic Fabry-Perot interferometers near fractional quantum Hall (FQH) filling factors 1/3, 2/3, 4/3 and 5/3 in the constrictions are compared to corresponding oscillations near integer quantum Hall (IQH) filling factors in the constrictions, appearing in the same devices and at the same gate voltages. Two-dimensional plots of resistance versus gate voltage and magnetic field indicate that all oscillations are Coulomb dominated. Applying a Coulomb charging model yields an effective tunneling charge e* \approx e/3 for all FQH constrictions and e* \approx e for IQH constrictions. Surprisingly, we find a common characteristic temperature for FQH oscillations and a different common characteristic temperature for IQH oscillations.