Rashbon condensation in a Bose gas with Rashba spin-orbit coupling

Abstract

We show that in a two-component Bose gas with Rashba spin-orbit coupling (SOC) two atoms can form bound states (Rashbons) with any intra-species scattering length. At zero center-of-mass momentum there are two degenerate Rashbons due to time-reversal symmetry, but the degeneracy is lifted at finite in-plane momentum with two different effective masses. A stable Rashbon condensation can be created in a dilute system with weakly attractive intra-species and repulsive inter-species interactions. The critical temperature of Rashbon condensation is about six times smaller than the BEC transition temperature of an ideal Bose gas. Due Rashba SOC, excitations in the Rashbon condensation phase are anisotropic in momentum space.

13 pages, 3 figures, text and figures updated

References in corpus (7)

• Spin-Injection Spectroscopy of a Spin-Orbit Coupled Fermi Gas
• Formation of Quantum-Degenerate Sodium Molecules
• Magnetically generated spin-orbit coupling for ultracold atoms
• Spin-orbit coupling and spin Hall effect for neutral atoms without spin-flips
• Stability of Excited Dressed States with Spin-Orbit Coupling
• Phase diagram of a Bose gas near a wide Feshbach resonance
• Molecular Bose-Einstein condensation in a Bose gas with a wide Feshbach resonance at finite temperatures

Cited by in corpus (7)

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• Spin-Orbit Coupling Induced Resonance in an Ultracold Bose Gas
• Energetics and structural properties of two- and three-boson systems in the presence of 1D spin-orbit coupling
• Critical temperature of pair condensation in a dilute Bose gas with spin-orbit coupling
• Bound-State Band Reconstruction and Resonance in Spin-1/2 Bose Gas with 1D Spin-Orbit Coupling
• Bardeen-Cooper-Schrieffer--type pairing in a spin-$\frac{1}{2}$ Bose gas with spin-orbit coupling