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The Transition Between Quantum Coherence and Incoherence

S. P. Strong
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Abstract

We show that a transformed Caldeira-Leggett Hamltonian has two distinct families of fixed points, rather than a single unique fixed point as often conjectured based on its connection to the anisotropic Kondo model. The two families are distinguished by a sharp qualitative difference in their quantum coherence properties and we argue that this distinction is best understood as the result of a transition in the model between degeneracy and non-degeneracy in the spectral function of the ``spin-flip'' operator.

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S. P. Strong. 1997-02-19. The Transition Between Quantum Coherence and Incoherence. https://doi.org/10.1103/physreve.55.6636

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