Fermion superfluid with hybridized $s$- and $p$-wave pairings

Abstract

Ever since the pioneering work of Bardeen, Cooper and Schrieffer in the 1950s, exploring novel pairing mechanisms for fermion superfluids has become one of the central tasks in modern physics. Here, we investigate a new type of fermion superfluid with hybridized $s$- and $p$-wave pairings in an ultracold spin-1/2 Fermi gas. Its occurrence is facilitated by the co-existence of comparable $s$- and $p$-wave interactions, which is realizable in a two-component ${}^{40}$K Fermi gas with close-by $s$- and $p$-wave Feshbach resonances. The hybridized superfluid state is stable over a considerable parameter region on the phase diagram, and can lead to intriguing patterns of spin densities and pairing fields in momentum space. In particular, it can induce a phase-locked $p$-wave pairing in the fermion species that has no $p$-wave interactions. The hybridized nature of this novel superfluid can also be confirmed by measuring the $s$-wave and $p$-wave contacts, which can be extracted from the high-momentum tail of the momentum distribution of each spin component. These results enrich our knowledge of pairing superfluidity in Fermi systems, and open the avenue for achieving novel fermion superfluids with multiple partial-wave scatterings in cold atomic gases.

7 pages, 5 figures, with more discussions and references added

References in corpus (18)

• Theory of ultracold Fermi gases
• Generalized Virial Theorem and Pressure Relation for a strongly correlated Fermi gas
• Resonantly-paired fermionic superfluids
• Exact Relations for a Strongly-interacting Fermi Gas from the Operator Product Expansion
• Verification of universal relations in a strongly interacting Fermi gas
• Universal Properties of the Ultra-Cold Fermi Gas
• Measurement of the Homogeneous Contact of a Unitary Fermi gas
• Mean field phase diagrams of imbalanced Fermi gases near a Feshbach resonance
• Anisotropic Fermi Superfluid via p-wave Feshbach Resonance
• Precise determination of the structure factor and contact in a unitary Fermi gas
• Induced P-wave Superfluidity in Asymmetric Fermi Gases
• Evidence for universal relations describing a gas with $p$-wave interactions
• Fermion Superfluids of Non-Zero Orbital Angular Momentum near Resonance
• Universal Properties of a Strongly Interacting Fermi Gas at a $p$-wave Resonance
• Universal high-momentum asymptote and thermodynamic relations in a spinless Fermi gas with a resonant $p$-wave interaction
• Concept of contact spectrum and its applications in atomic quantum Hall states
• Detecting the breached pair phase in a polarized ultracold Fermi gas
• Fermion Pairing across a Dipolar Interaction Induced Resonance

Cited by in corpus (11)

• Anapole superconductivity from $\mathcal{P}\mathcal{T}$-symmetric mixed-parity interband pairing
• $s$-wave Contacts of Quantum Gases in Quasi-one and Quasi-two Dimensions
• Single branch of chiral Majorana modes from doubly degenerate Fermi surfaces
• Universal Feature in Optical Control of a p-wave Feshbach Resonance
• P-wave contacts of quantum gases in quasi-one-dimensional and quasi-two-dimensional traps
• Universal relations and normal-state properties of a Fermi gas with laser-dressed mixed-partial-wave interactions
• Competition between pairing and tripling in one-dimensional fermions with coexistent s- and p-wave interactions
• Universal relations for hybridized $s$- and $p$-wave interactions from spin-orbital coupling
• Studies of Single Component Fermi Gas near a $P$-wave Resonance with Lowest Order Constrained Variational Method
• Shallow Trimers of Two Identical Fermions and One Particle in Resonant Regimes
• Mass-imbalance effect on the cluster formation in a one-dimensional Fermi gas with coexistent $s$- and $p$-wave interactions