Interface Dynamics of Strongly interacting Binary Superfluids

Abstract

Understanding the interface dynamics in non-equilibrium quantum systems remains a challenge. We study the interface dynamics of strongly coupled immiscible binary superfluids by using holographic duality. The full nonlinear evolution of the binary superfluids with a relative velocity shows rich nonlinear patterns toward quantum turbulence, which is reminiscent of the quantum Kelvin-Helmholtz instability. The wave number of the fast growing modes $k_0$ extracted from the interface pattern yields a non-monotonic dependence of the relative velocity, independent of the temperature and interaction. The value of $k_0$ first increases with the velocity difference and then decreases, which stands in sharp contrast to the results of mean-field theory described by the Gross-Pitaevskii equation and is confirmed by using the linear analyses on top of the stationary configuration. We uncover that the critical velocity associated with the maximum correspond to the case when the mean separation of vortices generated by interface instabilities becomes comparable to the vortex size, which could be a universal physical mechanism at strongly interacting superfluids and is directly testable in laboratory experiments.

Accepted version, 10 pages, 5 figures

References in corpus (7)

• Double species condensate with tunable interspecies interactions
• Dual-Species Bose-Einstein Condensate of ${}^{87}$Rb and ${}^{133}$Cs
• Defect formation beyond Kibble-Zurek mechanism and holography
• Universal far-from-equilibrium Dynamics of a Holographic Superconductor
• Inhomogeneous Structures in Holographic Superfluids: II. Vortices
• Competing Holographic Orders
• Heating up quadruply quantized vortices: Splitting patterns and dynamical transitions

Cited by in corpus (5)

• Suppression of the superfluid Kelvin-Helmholtz instability due to massive vortex cores, friction and confinement
• Quantum analog to flapping of flags: interface instability for co-flow binary superfluids
• Vortex shedding patterns in holographic superfluids at finite temperature
• (In)stability of symbiotic vortex-bright soliton in holographic immiscible binary superfluids
• Counterflow and coflow instabilities in miscible binary superfluids