Dissipative versus conditional generation of Gaussian entanglement and spin squeezing

  title={Dissipative versus conditional generation of Gaussian entanglement and spin squeezing},
  author={Denis V. Vasilyev and Christine A. Muschik and Klemens Hammerer},
  journal={Physical Review A},
Spin squeezing of collective atomic spins can be achieved conditionally via probing with light and subsequent homodyne detection, as is done in a Quantum Nondemolition measurement. Recently it has been shown that squeezing can also be created unconditionally by a properly designed dissipative dynamics. We compare the two approaches in a Gaussian description, and optimize over all Gaussian light-matter interactions. We find that in the optimal unconditional scheme based on dissipation the level… 

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