Pairing patterns in one-dimensional spin- and mass-imbalanced Fermi gases

Abstract

We study spin- and mass-imbalanced mixtures of spin-$\frac{1}{2}$ fermions interacting via an attractive contact potential in one spatial dimension. Specifically, we address the influence of unequal particle masses on the pair formation by means of the complex Langevin method. By computing the pair-correlation function and the associated pair-momentum distribution we find that inhomogeneous pairing is present for all studied spin polarizations and mass imbalances. To further characterize the pairing behavior, we analyze the density-density correlations in momentum space, the so-called shot noise, which is experimentally accessible through time-of-flight imaging. At finite spin polarization, the latter is known to show distinct maxima at momentum configurations associated with the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) instability. Besides those maxima, we find that additional features emerge in the noise correlations when mass imbalance is increased, revealing the stability of FFLO-type correlations against mass imbalance and furnishing an experimentally accessible signature to probe this type of pairing.

arXiv commentminor revisions to original version

References in corpus (65)

• Many-Body Physics with Ultracold Gases
• Theory of ultracold Fermi gases
• Fermionic Superfluidity with Imbalanced Spin Populations and the Quantum Phase Transition to the Normal State
• Fermi gases in one dimension: From Bethe Ansatz to experiments
• Probing many-body states of ultra-cold atoms via noise correlations
• Spatial quantum noise interferometry in expanding ultracold atom clouds
• Spin-Imbalance in a One-Dimensional Fermi Gas
• Quantum degenerate dipolar Fermi gas
• Observation of Phase Separation in a Strongly-Interacting Imbalanced Fermi Gas
• Probing Pair-Correlated Fermionic Atoms through Correlations in Atom Shot Noise
• BEC-BCS crossover in "magnetized" Feshbach-resonantly paired superfluids
• Attractive Fermi gases with unequal spin populations in highly elongated traps
• The Complex Langevin method: When can it be trusted?
• Imbalanced Feshbach-resonant Fermi gases
• Complex Langevin: Etiology and Diagnostics of its Main Problem
• Ultra-cold Polarized Fermi Gases
• Can stochastic quantization evade the sign problem? -- the relativistic Bose gas at finite chemical potential
• One-dimensional mixtures of several ultracold atoms: a review
• The argument for justification of the complex Langevin method and the condition for correct convergence
• The Fulde-Ferrell-Larkin-Ovchinnikov state for ultracold fermions in lattice and harmonic potentials: a review
• Mean field phase diagrams of imbalanced Fermi gases near a Feshbach resonance
• A Unitary Fermi Supersolid: The Larkin-Ovchinnikov Phase
• Exact Numerical Study of Pair Formation with Imbalanced Fermion Populations
• The FFLO state in the one-dimensional attractive Hubbard model and its fingerprint in the spatial noise correlations
• Experimental Characterization of Two-Particle Entanglement through Position and Momentum Correlations
• Imbalanced Fermi Gases at Unitarity
• Complex Langevin dynamics and zeroes of the fermion determinant
• Spin-1/2 fermions on spin-dependent optical lattices
• Lattice methods for strongly interacting many-body systems
• 1D to 3D Crossover of a Spin-Imbalanced Fermi Gas
• Commensurate mixtures of ultra-cold atoms in one dimension
• Phase structure of mass- and spin-imbalanced unitary Fermi gases
• Accurate Determination of the Dynamical Polarizability of Dysprosium
• Luttinger liquid of trimers in Fermi gases with unequal masses
• Quantum phase diagram of fermion mixtures with population imbalance in one-dimensional optical lattices
• Noise Correlations in low-dimensional systems of ultracold atoms
• Multi-particle composites in density-imbalanced quantum fluids
• Noise Correlations in one-dimensional systems of ultra-cold fermions
• Surmounting the sign problem in non-relativistic calculations: a case study with mass-imbalanced fermions
• Finite-temperature equation of state of polarized fermions at unitarity
• Hyperfine structure of laser-cooling transitions in fermionic erbium-167
• Third-order perturbative lattice and complex Langevin analyses of the finite-temperature equation of state of non-relativistic fermions in one dimension
• Quantum scattering in one dimension
• Evolution from few- to many-body physics in one-dimensional Fermi systems: One- and two-body density matrices, and particle-partition entanglement
• Asymptotic correlation functions and FFLO signature for the one-dimensional attractive spin-1/2 Fermi gas
• Universal phase diagram and scaling functions of imbalanced Fermi gases
• Inhomogeneous phases in one-dimensional mass- and spin-imbalanced Fermi gases
• Impenetrable Mass-Imbalanced Particles in One-Dimensional Harmonic Traps
• Pair formation and collapse in imbalanced Fermion populations with unequal masses
• Dimer, trimer and FFLO liquids in mass- and spin-imbalanced trapped binary mixtures in one dimension
• Few-fermion systems in one dimension: Ground- and excited-state energies and contacts
• Integrable families of hard-core particles with unequal masses in a one-dimensional harmonic trap
• Multimer formation in 1D two-component gases and trimer phase in the asymmetric attractive Hubbard model
• Realization of a Cold Mixture of Fermionic Chromium and Lithium Atoms
• Signatures of unconventional pairing in spin-imbalanced one-dimensional few-fermion systems
• Polarized fermions in one dimension: density and polarization from complex Langevin calculations, perturbation theory, and the virial expansion
• Bosonization study of quantum phase transitions in the one-dimensional asymmetric Hubbard model
• Phase separation and pairing regimes in the one-dimensional asymmetric Hubbard model
• Unconventional pairing in one-dimensional systems of a few mass-imbalanced ultracold fermions
• Fermi gases with imaginary mass imbalance and the sign problem in Monte Carlo calculations
• Pairing, crystallization and string correlations of mass-imbalanced atomic mixtures in one-dimensional optical lattices
• Spatial noise correlations of a chain of ultracold fermions - A numerical study
• Intercomponent correlations in attractive one-dimensional mass-imbalanced few-body mixtures
• Few-body physics on a space-time lattice in the worldline approach
• A complex Langevin approach to ultracold fermions

Cited by in corpus (16)

• Complex Langevin and other approaches to the sign problem in quantum many-body physics
• Magnetic impurity in a one-dimensional few-fermion system
• Pairing and the spin susceptibility of the polarized unitary Fermi gas in the normal phase
• Pairing patterns in polarized unitary Fermi gases above the superfluid transition
• Complex Langevin study for polarons in an attractively interacting one-dimensional two-component Fermi gas
• Unconventional pairing in few-fermion systems at finite temperature
• Low-Dimensional Fluctuations and Pseudogap in Gaudin-Yang Fermi Gases
• Few-body perspective on fermionic pairing in one spatial dimension
• Towards sampling complex actions
• BCS-BEC crossover of the strongly interacting ${}^6$Li-${}^{40}$K mixture
• Interplay of mass imbalance and frustration in correlated band insulators
• A lattice pairing-field approach to ultracold Fermi gases
• Unconventional pairing in few-fermion systems tuned by external confinement
• Strong Fulde-Ferrell Larkin-Ovchinnikov pairing fluctuations in polarized Fermi systems
• Current-induced re-entrant superconductivity and extreme nonreciprocal superconducting diode effect in valley-polarized systems
• Thermal liquid-gas phase transition in a quasi-one-dimensional dipolar Fermi gas