Instabilities in relativistic two-component (super)fluids

Abstract

We study two-fluid systems with nonzero fluid velocities and compute their sound modes, which indicate various instabilities. For the case of two zero-temperature superfluids we employ a microscopic field-theoretical model of two coupled bosonic fields, including an entrainment coupling and a non-entrainment coupling. We analyse the onset of the various instabilities systematically and point out that the dynamical two-stream instability can only occur beyond Landau's critical velocity, i.e., in an already energetically unstable regime. A qualitative difference is found for the case of two normal fluids, where certain transverse modes suffer a two-stream instability in an energetically stable regime if there is entrainment between the fluids. Since we work in a fully relativistic setup, our results are very general and of potential relevance for (super)fluids in neutron stars and, in the non-relativistic limit of our results, in the laboratory.

25 pages, 7 figures, v2: minor modifications; references added; parts of Sec III.B moved into new appendix B; version published in Phys. Rev. D

References in corpus (13)

• Color superconductivity in dense quark matter
• Models of Pulsar Glitches
• Transitions between turbulent and laminar superfluid vorticity states in the outer core of a neutron star
• Entrainment parameters in cold superfluid neutron star core
• Countersuperflow instability in miscible two-component Bose-Einstein condensates
• Flux tubes and the type-I/type-II transition in a superconductor coupled to a superfluid
• Relativistic BCS-BEC crossover in a boson-fermion model
• The relativistic entrainment matrix of a superfluid nucleon-hyperon mixture at zero temperature
• Stability conditions and Fermi surface topologies in a superconductor
• Counter-flow instability of a quantum mixture of two superfluids
• Critical velocities in two-component superfluid Bose gases
• Asymmetric Fermion Superfluid with Inter- and Intra-Species Pairings
• Collective excitation and stability of flow-induced gapless Fermi superfluids

Cited by in corpus (19)

• Relativistic fluid dynamics: physics for many different scales
• Critical magnetic fields in a superconductor coupled to a superfluid
• Thermodynamics of uncharged relativistic multifluids
• Chiral anomaly induces superconducting baryon crystal
• A superfluid perspective on neutron star dynamics
• Multicomponent meson superfluids in chiral perturbation theory
• Thermodynamic origin of the Landau instability of superfluids
• Spontaneous current in an holographic s+p superfluid
• From quasinormal modes of rotating black strings to hydrodynamics of a moving CFT plasma
• Small and hollow magnetic monopoles
• Hydrodynamic Stability Analysis of the Neutron Star Core
• Hydrodynamic attractor and novel fixed points in superfluid Bjorken flow
• Mixing of charged and neutral Bose condensates at nonzero temperature and magnetic field
• Many-body exceptional points in colliding condensates
• A relativistic two-stream instability in an extremely low-density plasma
• Roton instabilities in the superfluid outer core of neutron stars
• Multicomponent Superfluids and Superconductors in Dense Nuclear and Quark Matter
• Counterflow and coflow instabilities in miscible binary superfluids
• Thermodynamic stability of superflows in General Relativity and Newtonian gravity