Quantum Zeno effects across a parity-time symmetry breaking transition in atomic momentum space

  title={Quantum Zeno effects across a parity-time symmetry breaking transition in atomic momentum space},
  author={Tao Chen and Wei Gou and Dizhou Xie and Teng Xiao and Wei Yi and Jun Jing and Bo Yan},
  journal={npj Quantum Information},
We experimentally study quantum Zeno effects in a parity-time (PT) symmetric cold atom gas periodically coupled to a reservoir. Based on the state-of-the-art control of inter-site couplings of atoms in a momentum lattice, we implement a synthetic two-level system with passive PT symmetry over two lattice sites, where an effective dissipation is introduced through repeated couplings to the rest of the lattice. Quantum Zeno (anti-Zeno) effects manifest in our experiment as the overall dissipation… 

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