Measurement-induced Clock in a Lattice Ring of Non-interacting Electrons

David S. Schlegel; Stefan Kehrein

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arXiv · 2312.17672

Measurement-induced Clock in a Lattice Ring of Non-interacting Electrons

David S. Schlegel·Stefan Kehrein

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Abstract

We examine the emergence of periodicity in a non-interacting steady-state quantum system without external drive inspired by quantum time crystals' spontaneous time-translation symmetry breaking. Specifically, we consider a lattice ring of non-interacting electrons undergoing weak local position measurements. Our analysis uncovers time-periodic structures in steady-state two-time correlation functions, with periodicity linked to the system's group velocity. This study demonstrates a measurement-induced clock mechanism, highlighting periodic behaviors in two-time correlators of a non-equilibrium steady state, contributing to understanding time-periodic phenomena in minimally interactive quantum systems.

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David S. Schlegel, Stefan Kehrein. 2023-12-29. Measurement-induced Clock in a Lattice Ring of Non-interacting Electrons. https://arxiv.org/abs/2312.17672

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