Reentrant phase transition in the quantum anisotropic planar rotor model
Abstract
The quantum anisotropic planar rotor model was constructed to analyze the orientational behavior of homonuclear diatomics on inert surfaces. In this model and in related models involving coupled rotors, mean-field theory predicts a reentrant phase transition for intermediate values of the rotational constant. A reentrant phase transition is one in which the system reenters the disordered phase at low temperature. We have performed quantum Monte Carlo simulations combined with finite-size scaling concentrating on the parameter ranges where reentrance has been suspected to occur. We have found that reentrance is indeed present in the quantum anisotropic planar rotor model. Relying on comparisons with analytic models we argue that local (single-rotor) tunneling is resposible for the disordering of the system at low temperatures.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2001
- Bibcode:
- 2001APS..MARE10016H