Monte-Carlo simulations of the dissipative random transverse-field Ising chain

Manal Al-Ali; Thomas Vojta

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arXiv · 1307.7166

Monte-Carlo simulations of the dissipative random transverse-field Ising chain

Manal Al-Ali·Thomas Vojta

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Abstract

We study the influence of Ohmic dissipation on the random transverse-field Ising chain by means of large-scale Monte-Carlo simulations. To this end, we first map the Hamiltonian onto a classical Ising model with long-range $1/τ^2$ interaction in the time-like direction. We then apply the highly efficient cluster algorithm proposed by Luijten and Blöte for system with long-range interactions. Our simulations show that Ohmic dissipation destroys the infinite-randomness quantum critical point of the dissipationless system. Instead, the quantum phase transition between the paramagnetic and ferromagnetic phases is smeared. We compare our results to recent predictions of a strong-disorder renormalization group approach, and we discuss generalizations to higher dimensions as well as experiments.

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Manal Al-Ali, Thomas Vojta. 2013-07-26. Monte-Carlo simulations of the dissipative random transverse-field Ising chain. https://arxiv.org/abs/1307.7166

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