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arXiv · 0704.2496

Phase Boundary of the Boson Mott Insulator in a Rotating Optical Lattice

R. O. Umucalilar·M. O. Oktel
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Abstract

We consider the Bose-Hubbard model in a two dimensional rotating optical lattice and investigate the consequences of the effective magnetic field created by rotation. Using a Gutzwiller type variational wavefunction, we find an analytical expression for the Mott insulator(MI)-Superfluid(SF) transition boundary in terms of the maximum eigenvalue of the Hofstadter butterfly. The dependence of phase boundary on the effective magnetic field is complex, reflecting the self-similar properties of the single particle energy spectrum. Finally, we argue that fractional quantum Hall phases exist close to the MI-SF transition boundaries, including MI states with particle densities greater than one.

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R. O. Umucalilar, M. O. Oktel. 2007-04-19. Phase Boundary of the Boson Mott Insulator in a Rotating Optical Lattice. https://doi.org/10.1103/physreva.76.055601

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