Correlation effects in spin models in the presence of a spin bath

Álvaro Gómez-León; Tim Cox; Philip Stamp

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arXiv · 1811.07681

Correlation effects in spin models in the presence of a spin bath

Álvaro Gómez-León·Tim Cox·Philip Stamp

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Abstract

We analyze the effect of a bath of spins interacting with a spin system in terms of the equation of motion technique. We show that this formalism can be used with general spin systems and baths, and discuss the concrete case of a Quantum Ising model longitudinally coupled to the bath. We show how the uncorrelated solutions change when spin-spin correlations are included, the properties of the quasiparticle excitations and the effect of internal dynamics in the spin bath.

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Álvaro Gómez-León, Tim Cox, Philip Stamp. 2018-11-19. Correlation effects in spin models in the presence of a spin bath. https://arxiv.org/abs/1811.07681

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