Macroscopic superpositions in Bose-Josephson junctions: Controlling decoherence due to atom losses

@article{Pawowski2013MacroscopicSI,
  title={Macroscopic superpositions in Bose-Josephson junctions: Controlling decoherence due to atom losses},
  author={Krzysztof Pawłowski and D Spehner and Anna Minguzzi and G. Ferrini},
  journal={Physical Review A},
  year={2013},
  volume={88},
  pages={013606}
}
We study how macroscopic superpositions of coherent states produced by the nondissipative dynamics of binary mixtures of ultracold atoms are affected by atom losses. We identify different decoherence scenarios for symmetric or asymmetric loss rates and interaction energies in the two modes. In the symmetric case the quantum coherence in the superposition is lost after a single loss event. By tuning appropriately the energies we show that the superposition can be protected, leading to quantum… 

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References

SHOWING 1-10 OF 49 REFERENCES
Noise in Bose Josephson junctions: Decoherence and phase relaxation
Squeezed states and macroscopic superpositions of coherent states have been predicted to be generated dynamically in Bose Josephson junctions. We solve exactly the quantum dynamics of such a junction
Macroscopic superpositions of phase states with Bose-Einstein condensates
Quantum superpositions of macroscopically distinguishable states having distinct phases can be created with a Bose-Einstein condensate trapped in a periodic potential. The experimental signature is
Number squeezing, quantum fluctuations and oscillations in mesoscopic Bose Josephson junctions
Starting from a quantum two-mode Bose-Hubbard Hamiltonian we determine the ground state properties, momentum distribution and dynamical evolution for a Bose Josephson junction realized by an
Effect of phase noise on useful quantum correlations in Bose Josephson junctions
In a two-mode Bose-Josephson junction the dynamics induced by a sudden quench of the tunnel amplitude leads to the periodic formation of entangled states. For instance, squeezed states are formed at
Decoherence due to three-body loss and its effect on the state of a Bose-Einstein condensate.
  • M. Jack
  • Physics, Medicine
    Physical review letters
  • 2002
TLDR
A Born-Markov master equation is used to investigate the decoherence of the state of a macroscopically occupied mode of a cold atom trap due to three-body loss, and for large numbers of atoms (N>10(4)) theDecoherence time is found to be much faster than the phase-collapse time caused by intratrap atomic collisions.
Background atoms and decoherence in optical lattices
All experiments with ultracold atoms are performed in the presence of background residual gas. With the help of a suitable master equation we investigate a role of these fast atoms on the loss of
Spin squeezing in a bimodal condensate: spatial dynamics and particle losses
We propose an analytical method to study the entangled spatial and spin dynamics of interacting bimodal Bose-Einstein condensates. We show that at particular times during the evolution spatial and
Spin squeezing in Bose—Einstein condensates: Limits imposed by decoherence and non-zero temperature
We consider dynamically generated spin squeezing in interacting bimodal condensates. We show that particle losses and non-zero temperature effects in a multimode theory completely change the scaling
Effect of atom loss on collapse and revivals of phase coherence in small atomic samples
A small atomic sample at a single site of an optical lattice potential is a realization of an anharmonic oscillator with atomic collisions giving rise to the nonlinearity. Due to the atomic
Creation, detection, and decoherence of macroscopic quantum superposition states in double-well Bose-Einstein condensates
We study the possibility of creating many-particle macroscopic quantum superposition (Schr\"odinger cat)--like states by using a Feshbach resonance to reverse the sign of the scattering length of a
...
1
2
3
4
5
...