Monte Carlo simulations of dissipative quantum Ising models

Iver B. Sperstad; Einar B. Stiansen; Asle Sudbo

doi:10.1103/physrevb.81.104302

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arXiv · 1002.3369

Monte Carlo simulations of dissipative quantum Ising models

Iver B. Sperstad·Einar B. Stiansen·Asle Sudbo

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Abstract

The dynamical critical exponent $z$ is a fundamental quantity in characterizing quantum criticality, and it is well known that the presence of dissipation in a quantum model has significant impact on the value of $z$. Studying quantum Ising spin models using Monte Carlo methods, we estimate the dynamical critical exponent $z$ and the correlation length exponent $ν$ for different forms of dissipation. For a two-dimensional quantum Ising model with Ohmic site dissipation, we find $z \approx 2$ as for the corresponding one-dimensional case, whereas for a one-dimensional quantum Ising model with Ohmic bond dissipation we obtain the estimate $z \approx 1$.

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BibTeX RIS

Iver B. Sperstad, Einar B. Stiansen, Asle Sudbo. 2010-02-17. Monte Carlo simulations of dissipative quantum Ising models. https://doi.org/10.1103/physrevb.81.104302

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