Entanglement measures and nonequilibrium dynamics of quantum many-body systems: A path integral approach

  title={Entanglement measures and nonequilibrium dynamics of quantum many-body systems: A path integral approach},
  author={Roopayan Ghosh and Nicolas Dupuis and Arnab Sen and K. Sengupta},
  journal={Physical Review B},
We present a path integral formalism for expressing matrix elements of the density matrix of a quantum many-body system between any two coherent states in terms of standard Matsubara action with periodic(anti-periodic) boundary conditions on bosonic(fermionic) fields. We show that this enables us to express several entanglement measures for bosonic/fermionic many-body systems described by a Gaussian action in terms of the Matsubara Green function. We apply this formalism to compute various… 
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