Emergence of a pseudogap in the BCS-BEC crossover

Abstract

Strongly correlated Fermi systems with pairing interactions become superfluid below a critical temperature $T_c$. The extent to which such pairing correlations alter the behavior of the liquid at temperatures $T>T_c$ is a subtle issue that remains an area of debate, in particular regarding the appearance of the so-called pseudogap in the BCS-BEC crossover of unpolarized spin-$1/2$ nonrelativistic matter. To shed light on this, we extract several quantities of crucial importance at and around the unitary limit, namely: the odd-even staggering of the total energy, the spin susceptibility, the pairing correlation function, the condensate fraction, and the critical temperature $T_c$, using a non-perturbative, constrained-ensemble quantum Monte Carlo algorithm.

arXiv comment6 pages (including references), 4 figures; Added Journal Reference

References in corpus (65)

• Scikit-learn: Machine Learning in Python
• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Many-Body Physics with Ultracold Gases
• Feshbach Resonances in Ultracold Gases
• Theory of ultracold Fermi gases
• BCS-BEC Crossover: From High Temperature Superconductors to Ultracold Superfluids
• Revealing the Superfluid Lambda Transition in the Universal Thermodynamics of a Unitary Fermi Gas
• Large momentum part of fermions with large scattering length
• Energetics of a strongly correlated Fermi gas
• Superfluid Fermi Gases with Large Scattering Length
• Equation of state of a Fermi gas in the BEC-BCS crossover: a quantum Monte Carlo study
• The Unitary Fermi Gas: From Monte Carlo to Density Functionals
• Generalized Virial Theorem and Pressure Relation for a strongly correlated Fermi gas
• Extension of Bogoliubov theory to quasi-condensates
• The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems
• Quantum Monte Carlo Studies of Superfluid Fermi Gases
• Feynman diagrams versus Fermi-gas Feynman emulator
• Deviations from Fermi-liquid behavior above $T_c$ in 2D short coherence length superconductors
• Bayesian approach to model-based extrapolation of nuclear observables
• General relations for quantum gases in two and three dimensions. Two-component fermions
• Determination of the Superfluid Gap in Atomic Fermi Gases by Quasiparticle Spectroscopy
• Quantum Monte Carlo Simulations of the BCS-BEC Crossover at Finite Temperature
• Auxiliary Field quantum Monte Carlo for Strongly Paired Fermions
• Shell-model Monte Carlo studies of fp-shell nuclei
• Pairing correlations. Part 2: Microscopic analysis of odd-even mass staggering in nuclei
• Momentum distribution and condensate fraction of a Fermi gas in the BCS-BEC crossover
• Goldstone mode and pair-breaking excitations in atomic Fermi superfluids
• Quantified limits of the nuclear landscape
• Critical Temperature Curve in the BEC-BCS Crossover
• Exploring Bayesian parameter estimation for chiral effective field theory using nucleon-nucleon phase shifts
• Spectral response and contact of the unitary Fermi gas
• Speckle Imaging of Spin Fluctuations in a Strongly Interacting Fermi Gas
• Auxiliary-Field Quantum Monte Carlo Simulations of Neutron Matter in Chiral Effective Field Theory
• The edge of space: Revisiting the Karman Line
• Polarization Measurements and the Pairing Gap in the Universal Regime
• Complex Langevin and other approaches to the sign problem in quantum many-body physics
• Quantum mechanical limitations to spin diffusion in the unitary Fermi gas
• Demonstration of the auxiliary-field Monte Carlo approach for sd-shell nuclei
• Onset of a Pseudogap Regime in Ultracold Fermi Gases
• Enhanced paraconductivity-like fluctuations in the radio frequency spectra of ultracold Fermi atoms
• Contact and sum-rules in a near-uniform Fermi gas at unitarity
• Beyond the proton drip line: Bayesian analysis of proton-emitting nuclei
• Cooper pairing above the critical temperature in a unitary Fermi gas
• Pseudogaps in strongly interacting Fermi gases
• Contact and Momentum Distribution of the Unitary Fermi Gas
• The Equation of State of the Unitary Fermi Gas: An Update on Lattice Calculations
• Surmounting the sign problem in non-relativistic calculations: a case study with mass-imbalanced fermions
• Uniform spin susceptibility and spin-gap phenomenon in the BCS-BEC crossover regime of an ultracold Fermi gas
• The contact in the unitary Fermi gas across the superfluid phase transition
• Pairing correlations across the superfluid phase transition in the unitary Fermi gas
• Zero-temperature equation of state of mass-imbalanced resonant Fermi gases
• Imaginary polarization as a way to surmount the sign problem in ab initio calculations of spin-imbalanced Fermi gases
• The pseudogap regime in the unitary Fermi gas
• Projection of Good Quantum Numbers for Reaction Fragments
• Symmetry Obstruction to Fermi Liquid Behavior in the Unitary Limit
• Polarized fermions in one dimension: density and polarization from complex Langevin calculations, perturbation theory, and the virial expansion
• Strong-coupling corrections to spin susceptibility in the BCS-BEC crossover regime of a superfluid Fermi gas
• Polarized Fermi gases at finite temperature in the BCS-BEC crossover
• Improved lattice operators for non-relativistic fermions
• Thermal equation of state of polarized fermions in one dimension via complex chemical potentials
• Pair condensation in a Finite Trapped Fermi Gas
• Fermi gases with imaginary mass imbalance and the sign problem in Monte Carlo calculations
• Precursor Pairing Correlations and Pseudogaps
• Superfluid Condensate Fraction and Pairing Wave Function of the Unitary Fermi Gas
• Stabilizing Canonical-Ensemble Calculations in the Auxiliary-Field Monte Carlo Method

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