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arXiv · 2405.02103

Spectral density of complex eigenvalues and associated mean eigenvector self-overlaps at the edge of elliptic Ginibre ensembles

Mark J. Crumpton·Tim R. Würfel
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Abstract

We consider the density of complex eigenvalues, $\rho(z)$, and the associated mean eigenvector self-overlaps, $\mathcal{O}(z)$, at the spectral edge of $N \times N$ real and complex elliptic Ginibre matrices, as $N \to \infty$. Two different regimes of ellipticity are studied: strong non-Hermiticity, keeping the ellipticity parameter $\tau$ fixed and weak non-Hermiticity with $\tau \rightarrow 1 $ as $N \rightarrow \infty$. At strong non-Hermiticity, we find that both $\rho(z)$ and $\mathcal{O}(z)$ have the same leading order behaviour across the elliptic Ginibre ensembles, establishing the expected universality. In the limit of weak non-Hermiticity, we find different results for $\rho(z)$ and $\mathcal{O}(z)$ across the two ensembles. This paper is the final of three papers that we have presented addressing the mean self-overlap of eigenvectors in these ensembles.

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Mark J. Crumpton, Tim R. Würfel. 2024-05-03. Spectral density of complex eigenvalues and associated mean eigenvector self-overlaps at the edge of elliptic Ginibre ensembles. https://arxiv.org/abs/2405.02103

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