Josephson Effect in BEC with Spin Degree of Freedom
نویسندگان
چکیده
We consider the Josephson Effect between two spatially separated BoseEinstein condensates of atoms each of which can be in two hyperfine states. We derive simple equations of motion for this system closely analogous to the Bloch equations. We also map the dynamics of the system onto those of a classical particle in a well. We find novel density and spin modes of oscillation and new stable equilibrium points of the motion. Finally we analyze the oscillation modes in the spin-1 (F=1) case.
منابع مشابه
Modulational instability of spinor condensates
We demonstrate, analytically and numerically, that the ferromagnetic phase of the spinor Bose-Einstein condenstate may experience modulational instability of the ground state leading to a fragmentation of the spin domains. Together with other nonlinear effects in the atomic optics of ultra-cold gases (such as coherent photoassociation and four-wave mixing) this effect provides one more analogy ...
متن کاملMathematical models and numerical methods for spinor Bose-Einstein condensates
In this paper, we systematically review mathematical models, theories and numerical methods for ground states and dynamics of spinor Bose-Einstein condensates (BECs) based on the coupled Gross-Pitaevskii equations (GPEs). We start with a pseudo spin-1/2 BEC system with/without an internal atomic Josephson junction and spin-orbit coupling including (i) existence and uniqueness as well as non-exi...
متن کاملSpin Josephson effect in ferromagnet/ferromagnet tunnel junctions
– We consider the tunnel current between two ferromagnetic metals from a perspective similar to the one used in superconductor/superconductor tunnel junctions. We use fundamental arguments to derive a Josephson-like tunnel spin current I J ∝ sin(θ1 − θ2). Here the phases are associated with the planar contribution to the magnetization, 〈c†↑c↓〉 ∼ e . The crucial step in our analysis is the fact ...
متن کاملA simple method to create a vortex in Bose-Einstein condensate of alkali atoms
Bose-Einstein condensation in alkali atoms has materialized quite an interesting system, namely a condensate with a spin degree of freedom. In analogy with the A-phase of the superfluid He, numerous textures with nonvanishing vorticity have been proposed. In the present paper, interesting properties of such spin textures are analyzed. We propose a remarkably simple method to create a vortex sta...
متن کاملStability of a Vortex in Spinor Bose-Einstein Condensate
We propose a method to create a vortex in BEC utilizing the spin degree of freedom. We consider the optical plug at the center of the vortex, which makes the vortex-creation process stable. We also investigate the instability of the halfway state to complete vortex state without the optical plug.
متن کامل