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arXiv · 1812.01907

Revealing the nature of non-equilibrium phase transitions with quantum trajectories

Valentin Link·Kimmo Luoma·Walter T. Strunz
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Abstract

A damped and driven collective spin system is analyzed by using quantum state diffusion. This approach allows for a mostly analytical treatment of the investigated non-equilibrium quantum many body dynamics, which features a phase transition in the thermodynamical limit. The exact results obtained in this work, which are free of any finite size defects, provide a complete understanding of the model. Moreover, the trajectory framework gives an intuitive picture of the two phases occurring, revealing a spontaneously broken symmetry and allowing for a qualitative and quantitative characterization of the phases. We determine exact critical exponents, investigate finite size scaling, and explain a remarkable non-algebraic behaviour at the transition in terms of torus hopping.

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Valentin Link, Kimmo Luoma, Walter T. Strunz. 2018-12-05. Revealing the nature of non-equilibrium phase transitions with quantum trajectories. https://doi.org/10.1103/physreva.99.062120

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