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Quantum Phase Transitions of Hard-Core Bosons in Background Potentials

Anand Priyadarshee·Shailesh Chandrasekharan·Ji-Woo Lee·Harold U. Baranger
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Abstract

We study the zero temperature phase diagram of hard core bosons in two dimensions subjected to three types of background potentials: staggered, uniform, and random. In all three cases there is a quantum phase transition from a superfluid (at small potential) to a normal phase (at large potential), but with different universality classes. As expected, the staggered case belongs to the XY universality, while the uniform potential induces a mean field transition. The disorder driven transition is clearly different from both; in particular, we find z~1.4, ν~1, and β~0.6.

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Anand Priyadarshee, Shailesh Chandrasekharan, Ji-Woo Lee, Harold U. Baranger. 2006-09-14. Quantum Phase Transitions of Hard-Core Bosons in Background Potentials. https://doi.org/10.1103/physrevlett.97.115703

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