Generation of directional, coherent matter beams through dynamical instabilities in Bose-Einstein condensates

Abstract

We present a theoretical analysis of a coupled, two-state Bose-Einstein condensate with non-equal scattering lengths, and show that dynamical instabilities can be excited. We demonstrate that these instabilities are exponentially amplified resulting in highly-directional, oppositely-propagating, coherent matter beams at specific momenta. To accomplish this we prove that the mean field of our system is periodic, and extend the standard Bogoliubov approach to consider a time-dependent, but cyclic, background. This allows us to use Floquet's theorem to gain analytic insight into such systems, rather than employing the usual Bogoliubov-de Gennes approach, which is usually limited to numerical solutions. We apply our theory to the metastable Helium atom laser experiment of Dall et al. [Phys. Rev. A 79, 011601(R) (2009)] and show it explains the anomalous beam profiles they observed. Finally we demonstrate the paired particle beams will be EPR-entangled on formation.

Corrected references

References in corpus (12)

• Many-Body Physics with Ultracold Gases
• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Squeezing and entanglement in a Bose-Einstein condensate
• Universality in Three- and Four-Body Bound States of Ultracold Atoms
• Finite Temperature Models of Bose-Einstein Condensation
• Precision measurement of spin-dependent interaction strengths for spin-1 and spin-2 87Rb atoms
• Observation of atom pairs in spontaneous four wave mixing of two colliding Bose-Einstein Condensates
• Generating squeezing in an atom laser through self-interaction
• Paired atom laser beams created via four-wave mixing
• Atom-atom correlations in colliding Bose-Einstein condensates
• Correlated directional atomic clouds via four-heterowave mixing
• A two-state Raman coupler for coherent atom optics

Cited by in corpus (5)

• Improving cold-atom sensors with quantum entanglement: Prospects and challenges
• Self-induced Spatial Dynamics to Enhance Spin-Squeezing via One-Axis Twisting in a Two-Component Bose-Einstein Condensate
• Surpassing the Standard Quantum Limit in an Atom Interferometer with Four-mode Entanglement Produced from Four-Wave Mixing
• Squeezing in Bose-Einstein condensates with large numbers of atoms
• Tradeoffs for number-squeezing in collisions of Bose-Einstein condensates