Non-Hermitian Bloch Oscillations

Yanyan He; Tomoki Ozawa

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arXiv · 2606.26480

Non-Hermitian Bloch Oscillations

Yanyan He·Tomoki Ozawa

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Abstract

We establish a general framework for non-Hermitian Bloch oscillations by investigating the wave-packet dynamics in one-dimensional non-Hermitian lattices driven by a dc force. The equations of motion for the momentum, center of mass, and group velocity of a wave packet are derived, where an anomalous group velocity due to the non-Hermiticity is identified. We show that nonreciprocal non-smooth Bloch oscillations, characterized by periodic jumps in group velocity, can emerge, and we analyze the role of finite-size effects. In non-Hermitian lattices with unidirectional hopping under open boundary conditions, we further uncover the emergence of periodic temporal Goos--H\"anchen shifts together with an anomalous wave propagation along the direction of vanishing hopping.

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Yanyan He, Tomoki Ozawa. 2026-06-25. Non-Hermitian Bloch Oscillations. https://arxiv.org/abs/2606.26480

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