Category: Physics

Summary: Testing whether short-range anti-correlated disorder lowers the Hatano-Nelson delocalization threshold below the independent-disorder baseline.

Correlations in disorder can change localization behavior even when the overall variance stays fixed. This experiment asks what happens in the non-Hermitian Hatano-Nelson chain when diagonal disorder is strongly anti-correlated from site to site rather than independent.

The model generates dense non-Hermitian matrices with AR(1)-style negative disorder correlations and then bisects the disorder level across increasing sizes. It measures how the critical transition point shifts relative to the better-known independent and positively correlated cases.

This makes the experiment a targeted comparison, not just another sweep of the same model. It probes whether alternating high-low structure makes delocalization more fragile in biased disordered transport.

Method: Dense non-Hermitian eigensolve with iterative deepening and bisection on anti-correlated disorder strength in a Hatano-Nelson chain.

What is measured: Critical disorder threshold, shift relative to the IID baseline, spectral delocalization indicator, and bracket width.