Smeared quantum phase transition in the dissipative random quantum Ising model

Thomas Vojta; J. A. Hoyos

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arXiv · 0811.3754

Smeared quantum phase transition in the dissipative random quantum Ising model

Thomas Vojta·J. A. Hoyos

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Abstract

We investigate the quantum phase transition in the random transverse-field Ising model under the influence of Ohmic dissipation. To this end, we numerically implement a strong-disorder renormalization-group scheme. We find that Ohmic dissipation destroys the quantum critical point and the associated quantum Griffiths phase by smearing. Our results quantitatively confirm a recent theory [Phys. Rev. Lett. {\bf 100}, 240601 (2008)] of smeared quantum phase transitions.

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Thomas Vojta, J. A. Hoyos. 2010-01-18. Smeared quantum phase transition in the dissipative random quantum Ising model. https://arxiv.org/abs/0811.3754

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