Periodic dynamics of fermionic superfluids in the BCS regime

Abstract

We study the zero temperature non-equilibrium dynamics of a fermionic superfluid in the BCS limit and in the presence of a drive leading to a time dependent chemical potential $\mu (t)$. We choose a periodic driving protocol characterized by a frequency $\omega$ and compute the fermion density, the wavefunction overlap, and the residual energy of the system at the end of $N$ periods of the drive. We demonstrate that the BCS self-consistency condition is crucial in shaping the long-time behaviour of the fermions subjected to the drive and provide an analytical understanding of the behaviour of the fermion density $n_{{\mathbf{k}}_F}$ (where ${\mathbf{k}}_F$ is the Fermi momentum vector) after a drive period and for large $\omega$. We also show that the momentum distribution of the excitations generated due to such a drive bears the signature of the pairing symmetry and can be used, for example, to distinguish between s- and d-wave superfluids. We propose experiments to test our theory.

v1, 10+ pages, 8 figs. Cosmetic changes from the previous version

References in corpus (21)

• Many-Body Physics with Ultracold Gases
• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Thermalization and its mechanism for generic isolated quantum systems
• Theory of ultracold Fermi gases
• Vortices and Superfluidity in a Strongly Interacting Fermi Gas
• Creating, moving and merging Dirac points with a Fermi gas in a tunable honeycomb lattice
• Spontaneous symmetry breaking in a quenched ferromagnetic spinor Bose condensate
• Quantum Simulation of Antiferromagnetic Spin Chains in an Optical Lattice
• Observation of the Pairing Gap in a Strongly Interacting Fermi Gas
• Weakly bound dimers of fermionic atoms
• Collective excitations of a degenerate gas at the BEC-BCS crossover
• Universal adiabatic dynamics across a quantum critical point
• Thermodynamics of the BCS-BEC crossover
• Supplementary Information to the paper ``Breakdown of the adiabatic limit in low dimensional gapless systems''
• Breakdown of the adiabatic limit in low dimensional gapless systems
• Defect production in non-linear quench across a quantum critical point
• BCS-BEC crossover at finite temperature in the broken-symmetry phase
• Quench dynamics and defect production in the Kitaev and extended Kitaev models
• Transverse Ising Chain under Periodic Instantaneous Quenches: Dynamical Many-Body Freezing and Emergence of Solitary Oscillation
• A projection operator approach to the Bose-Hubbard model
• Sign-free stochastic mean-field approach to strongly correlated phases of ultracold fermions

Cited by in corpus (3)

• A Novel Route to Reach a $p$-wave Superfluid Fermi Gas
• Nonequilibrium Dynamics of Ultracold Fermi Superfluids
• Appropriate conditions to realize a $p$-wave superfluid state starting from a spin-orbit coupled $s$-wave superfluid Fermi gas