Abstract
We discuss the topological superfluid phase in a two-dimensional (2D) gas of single-component fermionic polar molecules dressed by a circularly polarized microwave field. This phase emerges because the molecules may interact with each other via a potential that has an attractive dipole-dipole tail, which provides -wave superfluid pairing at fairly high temperatures. We calculate the amplitude of elastic -wave scattering in the potential taking into account both the anomalous scattering due to the dipole-dipole tail and the short-range contribution. This amplitude is then used for the analytical and numerical solution of the renormalized BCS gap equation which includes the second-order Gor’kov-Melik-Barkhudarov corrections and the correction related to the effective mass of the quasiparticles. We find that the critical temperature can be varied within a few orders of magnitude by modifying the short-range part of the potential . The decay of the system via collisional relaxation of molecules to dressed states with lower energies is rather slow due to the necessity of a large momentum transfer. The presence of a constant transverse electric field reduces the inelastic rate, and the lifetime of the system can be of the order of seconds even at 2D densities cm. This leads to of up to a few tens of nanokelvins and makes it realistic to obtain the topological phase in experiments with ultracold polar molecules.
2 More- Received 20 March 2011
DOI:https://doi.org/10.1103/PhysRevA.84.013603
©2011 American Physical Society
Synopsis
A new phase for molecular superfluidity
Published 8 July 2011
Theoretical analysis shows how exotic superfluidity might be observed in ultracold molecules.
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