arXiv:cond-mat/0611394 · Physical Review Letters

Quantum Phase Transitions of Polar Molecules in Bilayer Systems

Daw-Wei Wang

Published Feb 7, 2007• 58 citations

Abstract

We investigate the quantum phase transitions of bosonic polar molecules in a two-dimensional double layer system. We show that an interlayer bound state of dipoles (dimers) can be formed when the dipole strength is above a critical value, leading to a zero-energy resonance in the interlayer s-wave scattering channel. In the positive detuning side of the resonance, the strong repulsive interlayer pseudopotential can drive the system into a maximally entangled state, where the wave function is a superposition of two states that have all molecules in one layer and none in the other. We discuss how the zero-energy resonance, dimer states, and the maximally entangled state can be measured in time-of-flight experiments.

DOI: 10.1103/physrevlett.98.060403

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