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arXiv · 2509.16747

$\Delta_T$ Noise as a Robust Diagnostic for Chiral, Helical and Trivial Edge Modes

Sachiraj Mishra·Colin Benjamin
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Abstract

In this article, we demonstrate that $\Delta_T$ noise provides a sensitive, practical probe for distinguishing chiral edge modes from topological helical and trivial (non-topological) helical edge transport. Measured under zero-current conditions, $\Delta_T$ noise reveals contrasts that conventional conductance measurements typically miss. Crucially, $\Delta_T$ noise requires no external energy input in the form of an applied voltage bias, yet encodes the same intrinsic information that shot noise yields in the zero-temperature, finite-bias limit, without the distorting effects of Joule heating. This absence of bias-induced heating makes $\Delta_T$ noise both more precise and more reliable than conventional shot-noise approaches.

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Sachiraj Mishra, Colin Benjamin. 2025-09-20. $\Delta_T$ Noise as a Robust Diagnostic for Chiral, Helical and Trivial Edge Modes. https://doi.org/10.1088/1361-648x%2Fae8493

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