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arXiv · 2205.09367

Spin-spin coupling-based quantum and classical phase transitions in two-impurity spin-boson models

Roberto Grimaudo·Antonino Messina·Hiromichi Nakazato·Alessandro Sergi·Davide Valenti
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Abstract

The class of two-interacting-impurity spin-boson models with vanishing transverse fields on the spin-pair is studied. The model can be exactly mapped into two independent standard single-impurity spin-boson models where the role of the tunnelling parameter is played by the spin-spin coupling. The dynamics of the magnetization is analysed for different levels of (an)isotropy. Further, the existence of a decoherence-free subspace as well as of both classical and quantum (first-order and Kosterlitz-Thouless type) phase transitions, in the Omhic regime, is brought to light.

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Roberto Grimaudo, Antonino Messina, Hiromichi Nakazato, Alessandro Sergi, Davide Valenti. 2022-05-19. Spin-spin coupling-based quantum and classical phase transitions in two-impurity spin-boson models. https://arxiv.org/abs/2205.09367

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