Entangled Superfluids

Abstract

We study the condensate dynamics of the so-called entangled Bose-Einstein condensation (EBEC), which is the ground state of a mixture of two species of pseudospin-$\frac{1}{2}$ atoms with interspecies spin-exchange scattering in certain parameter regimes. EBEC leads to four inter-dependent superfluid components, each corresponding to the orbital wave function associated with a spin component of a species. The four superflows have various counter-relations, and altogether lead to a conserved total supercurrent and a conserved total spin supercurrent. In the homogenous case, we also obtain the elementary excitations due to variations of the single-particle orbital wave functions, by exactly solving the generalized time-dependent Bogoliubov equations. There are three gapless Bogoliubov modes and one Klein-Gordon-like gapped mode. The origin of these excitations are also discussed from the perspective of spontaneous breaking of the symmetries possessed by the system.

10 pages. Published in PRA

References in corpus (3)

• Spontaneous symmetry breaking in a quenched ferromagnetic spinor Bose condensate
• Double species condensate with tunable interspecies interactions
• Bose-Einstein Condensation with Entangled Order Parameter

Cited by in corpus (8)

• Ground States of a Mixture of Two Species of Spinor Bose Gases with Interspecies Spin Exchange
• Three-dimensional quantum phase diagram of the exact ground states of a mixture of two species of spin-1 Bose gases with interspecies spin exchange
• Ground states of a mixture of two species of spin-1 Bose gases with interspecies spin exchange in a magnetic field
• Binary mixture of pseudospin-1/2 Bose gases with interspecies spin exchange: from classical fixed points and ground states to quantum ground states
• Orbital elementary excitations as probes of entanglement and quantum phase transitions of collective spins in an entangled Bose-Einstein condensate
• Polarized entangled Bose-Einstein condensation
• Number and spin densities in the ground state of a trapped mixture of two pseudospin-1/2 Bose gases with interspecies spin-exchange interaction
• Sine-Gordon model coupled with a free scalar field emergent in the low-energy phase dynamics of a mixture of pseudospin-1/2 Bose gases with interspecies spin exchange