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Different Fractional Charges from Auto- and Cross-Correlation Noise in Quantum Hall States without Upstream Modes
1Department of Physics, <a href="https://ror.org/05gq02987">Brown University</a>, Providence, Rhode Island 02912, USA and Brown Theoretical Physics Center, <a href="https://ror.org/05gq02987">Brown University</a>, Providence, Rhode Island 02912, USA.
Physical Review Letters
|June 15, 2024
Summary
Shot noise measurements can detect fractional charges in anyons. A new mechanism explains excess noise in autocorrelation measurements, even without upstream edge modes, providing a more accurate charge determination.
Area of Science:
- Condensed matter physics
- Quantum Hall effect
Background:
- Shot noise measurements are a key technique for detecting fractional charges in anyons.
- Existing methods using autocorrelation noise often overestimate the charge due to upstream edge modes.
Purpose of the Study:
- To propose a novel mechanism for excess autocorrelation noise in anyon systems.
- To explain the overestimation of fractional charges in certain shot noise measurements.
Main Methods:
- Theoretical analysis of shot noise in systems with multiple copropagating edge modes.
- Focus on noise measurements at low, nonzero frequencies.
Main Results:
- A mechanism for excess autocorrelation noise is identified, independent of upstream edge modes.
- The proposed mechanism is applicable to systems with multiple copropagating edge modes.
Conclusions:
- The study provides a new understanding of shot noise in anyon systems.
- This work offers a path towards more accurate measurements of fractional charges.
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