BCS-BEC Crossover in Bilayers of Cold Fermionic Polar Molecules

Abstract

We investigate the quantum and thermal phase diagram of fermionic polar molecules loaded in a bilayer trapping potential with perpendicular dipole moment. We use both a BCS theory approach that is most realiable at weak-coupling and a strong-coupling approach that considers the two-body bound dimer states with one molecules in each layer as the relevant degree of freedom. The system ground state is a Bose-Einstein condensate (BEC) of dimer bound states in the low density limit and a paired superfluid (BCS) state in the high density limit. At zero temperature, the intralayer repulsion is found to broaden the regime of BCS-BEC crossover, and can potentially induce system collapse through the softening of roton excitations. The BCS theory and the strongly-coupled dimer picture yield similar predictions for the parameters of the crossover regime. The BKT transition temperature of the dimer superfluid is also calculated. The crossover can be driven by many-body effects and is strongly affected by the intralayer interaction which was ignored in previous studies.

arXiv comment6 pages, 3 figures, final version

References in corpus (41)

• A High Phase-Space-Density Gas of Polar Molecules
• The physics of dipolar bosonic quantum gases
• Berezinskii-Kosterlitz-Thouless Crossover in a Trapped Atomic Gas
• Quantum-State Controlled Chemical Reactions of Ultracold KRb Molecules
• Formation of ultracold polar molecules in the rovibrational ground state
• Dipolar collisions of polar molecules in the quantum regime
• Roton-maxon spectrum and stability of trapped dipolar condensates
• Strongly correlated 2D quantum phases with cold polar molecules: controlling the shape of the interaction potential
• Controlling the quantum stereodynamics of ultracold bimolecular reactions
• Ultracold Molecules in the Ro-Vibrational Triplet Ground State
• Ultracold dense gas of deeply bound heteronuclear molecules
• Quantum phase transition in a two-dimensional system of dipoles
• Stable Topological Superfluid Phase of Ultracold Polar Fermionic Molecules
• Stability of quasi-two-dimensional Bose-Einstein condensates with dominant dipole-dipole interactions
• BCS-BEC crossover in a two-dimensional Fermi gas
• Quantum fluids of self-assembled chains of polar molecules
• Quantum phases of a Two-Dimensional Dipolar Fermi Gas
• Interlayer superfluidity in bilayer systems of fermionic polar molecules
• Berezinskii-Kosterlitz-Thouless transition in two-dimensional dipole systems
• Bilayer superfluidity of fermionic polar molecules: many body effects
• Density wave instability in a 2D dipolar Fermi gas
• Two-dimensional scattering and bound states of polar molecules in bilayers
• Superfluidity and dimerization in a multilayered system of fermionic polar molecules
• Spontaneous inhomogeneous phases in ultracold dipolar Fermi gases
• Quantum phase transitions of polar molecules in bilayer systems
• Quantum melting of a crystal of dipolar bosons
• Few-body bound states in dipolar gases and their detection
• Collective modes, stability and superfluid transition of a quasi-two-dimensional dipolar Fermi gas
• The permanent dipole moment of LiCs in the ground state
• Superfluid Bosons and Flux Liquids: Disorder, Thermal Fluctuations, and Finite-Size Effects
• Model independence in two dimensions and polarized cold dipolar molecules
• Bound States and Universality in Layers of Cold Polar Molecules
• Pseudo-potential of a power-law decaying interaction in two-dimensional systems
• Hartree-Fock-Bogoliubov Theory of Dipolar Fermi Gases
• Bose-Fermi mixtures of self-assembled filaments of fermionic polar molecules
• Density Waves in Layered Systems with Fermionic Polar Molecules
• Density ordering instabilities of quasi-two-dimensional fermionic polar molecules in single-layer and multi-layer configurations: exact treatment of exchange interactions
• Spontaneous interlayer superfluidity in bilayer systems of cold polar molecules
• Few-Body Bound Complexes in One-dimensional Dipolar Gases and Non-Destructive Optical Detection
• Bound Dimers in Bilayers of Cold Polar Molecules
• Interaction induced ferro-electricity in the rotational states of polar molecules

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• Condensed Matter Theory of Dipolar Quantum Gases
• Zero-point energy of ultracold atoms
• Collective modes, stability and superfluid transition of a quasi-two-dimensional dipolar Fermi gas
• Analytic Harmonic Approach to the N-body problem
• Reactions Between Layer-Resolved Molecules Mediated by Dipolar Exchange
• Finite-temperature quantum fluctuations in two-dimensional Fermi superfluids
• Density Waves in Layered Systems with Fermionic Polar Molecules
• Novel Fermi Liquid of 2D Polar Molecules
• Density wave instabilities of tilted fermionic dipoles in a multilayer geometry
• Novel $p$-wave superfluids of fermionic polar molecules
• Dipolar-Induced Resonance for Ultracold Bosons in a Quasi-1D Optical Lattice
• Few-body bound state stability of dipolar molecules in two dimensions
• Bound states of Dipolar Bosons in One-dimensional Systems
• Quantum Many-Body Physics with Ultracold Polar Molecules: Nanostructured Potential Barriers and Interactions
• Virial expansion coefficients in the harmonic approximation
• Layers of Cold Dipolar Molecules in the Harmonic Approximation
• Fixed-node diffusion Monte Carlo study of the BCS-BEC crossover in a bilayer system of fermionic dipoles
• Quantum Statistics and Thermodynamics in the Harmonic Approximation
• Density-wave phases of dipolar fermions in a bilayer
• Dimers, Effective Interactions, and Pauli Blocking Effects in a Bilayer of Cold Fermionic Polar Molecules
• Unconventional superfluids of fermionic polar molecules in a bilayer system
• Occurrence conditions for two-dimensional Borromean systems
• Parafermion excitations in superfluid of quasi-molecular chains
• Effective dipole-dipole interactions in multilayered dipolar Bose-Einstein condensates
• Optical probing in a bilayer dark-bright condensate system
• Zero sound in a two-dimensional dipolar Fermi gas
• Dipoles on a Two-leg Ladder
• Fulde-Ferrell-Larkin-Ovchinnikov state in bilayer dipolar systems
• Second-order interaction corrections to the Fermi surface and the quasiparticle properties of dipolar fermions in three dimensions
• Phase diagram of two-component dipolar fermions in one-dimensional optical lattices
• Quantum phases of quadrupolar Fermi gases in coupled one-dimensional systems
• Supersolid phases of dipolar fermions in a two-dimensional-lattice bilayer array
• Thermodynamics of Dipolar Chain Systems
• Superfluidity of a dipolar Fermi gas in 2D optical lattices bilayer
• Bound Chains of Tilted Dipoles in Layered Systems
• Kohn-Sham approach to Fermi gas superfluidity: the bilayer of fermionic polar molecules
• A local exchange theory for trapped dipolar gases
• Superfluidity in density imbalanced bilayers of dipolar fermions
• Interplay of interlayer pairing and many-body screening in a bilayer of dipolar fermions
• Quantum gas of polar molecules ensembles at ultralow temperatures: f-wave superfluids
• Classical crystal formation of dipoles in two dimensions
• Many-Body Formation and Dissociation of a Dipolar Chain Crystal
• Mixed parity pairing in a dipolar gas
• Emergent interlayer nodal superfluidity of a dipolar fermi gas in bilayer optical lattices
• Vortex generation in a superfluid gas of dipolar chains in crossed electric and magnetic fields
• Phase Diagram of a Spin-Orbit Coupled Fermi Gases in a Bilayer Optical Lattice
• Quantum Degenerate Majorana Surface Zero Modes in Two-Dimensional Space
• 2D Gapless Topological Superfluids Generated by Pairing Phases