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arXiv · 2602.21451

Topological phase dynamics described by overtone-synthesized classical and quantum Adler equations

Hiroshi Yamaguchi·Motoki Asano
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Abstract

The Adler equation is a well-known one-dimensional model describing phase locking and synchronization. Motivated by recent experiments using optomechanical oscillators, we extend the model to include overtone-synthesized sinusoidal coupling with adiabatic temporal modulation. This extension gives rise to unique topological features such as winding-number quantization, discontinuous phase-slip transitions, and hysteretic and non-reciprocal phase dynamics. We further extend the analysis to the quantum regime, where we find a counterintuitive result: the breakdown of winding-number quantization. This arises from the superposition of different winding-number states in a closed-space Thouless pump. Moreover, hysteretic dynamics, once eliminated in quantum adiabatic approximation, is recovered in non-adiabatic calculations, as the superposition of two Floquet states with different PT eigenvalues becomes the quantum counterpart of phase trajectory.

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Hiroshi Yamaguchi, Motoki Asano. 2026-02-25. Topological phase dynamics described by overtone-synthesized classical and quantum Adler equations. https://doi.org/10.1103/vcqz-m2r1

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