Variational quantum algorithm for nonequilibrium steady states

  title={Variational quantum algorithm for nonequilibrium steady states},
  author={Nobuyuki Yoshioka and Yuya O Nakagawa and Kosuke Mitarai and Keisuke Fujii},
  journal={arXiv: Quantum Physics},
We propose a quantum-classical hybrid algorithm to simulate the non-equilibrium steady state of an open quantum many-body system, named the dissipative-system Variational Quantum Eigensolver (dVQE). To employ the variational optimization technique for a unitary quantum circuit, we map a mixed state into a pure state with a doubled number of qubits and design the unitary quantum circuit to fulfill the requirements for a density matrix. This allows us to define a cost function that consists of… Expand

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