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arXiv · 2309.00945

Spectral analysis and phase transitions for long-range interactions in harmonic chains of oscillators

Simon Becker·Angeliki Menegaki·Jiming Yu
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Abstract

We consider chains of $N$ harmonic oscillators in two dimensions coupled to two Langevin heat reservoirs at different temperatures - a classical model for heat conduction introduced by Lebowitz, Lieb, and Rieder \cite{RLL67}. We extend our previous results \cite{BM20} significantly by providing a full spectral description of the full Fokker-Planck operator allowing also for the presence of a constant external magnetic field for charged oscillators. We then study oscillator chains with additional next-to-nearest-neighbor interactions and find that the spectral gap undergoes a phase transition if the next-to-nearest-neighbour interactions are sufficiently strong and may even cease to exist for oscillator chains of finite length.

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Simon Becker, Angeliki Menegaki, Jiming Yu. 2023-09-02. Spectral analysis and phase transitions for long-range interactions in harmonic chains of oscillators. https://arxiv.org/abs/2309.00945

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