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arXiv · 2301.07370

Phase transitions of wave packet dynamics in disordered non-Hermitian systems

Helene Spring·Viktor Könye·Fabian A. Gerritsma·Ion Cosma Fulga·Anton R. Akhmerov
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Abstract

Disorder can localize the eigenstates of one-dimensional non-Hermitian systems, leading to an Anderson transition with a critical exponent of 1. We show that, due to the lack of energy conservation, the dynamics of individual, real-space wave packets follows a different behavior. Both transitions between localization and unidirectional amplification, as well as transitions between distinct propagating phases become possible. The critical exponent of the transition equals $1/2$ in propagating-propagating transitions.

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Helene Spring, Viktor Könye, Fabian A. Gerritsma, Ion Cosma Fulga, Anton R. Akhmerov. 2023-01-18. Phase transitions of wave packet dynamics in disordered non-Hermitian systems. https://doi.org/10.21468/scipostphys.16.5.120

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