Tempel, DavidAspuru-Guzik, Alan2016-11-182014Tempel, David G, and Alán Aspuru-Guzik. 2014. The Kitaev–Feynman Clock for Open Quantum Systems. New J. Phys. 16 (11) (November 26): 113066. doi:10.1088/1367-2630/16/11/113066.1367-2630http://nrs.harvard.edu/urn-3:HUL.InstRepos:29407536We show that Kitaevʼs construction of Feynmanʼs clock, in which the time-evolution of a closed quantum system is encoded as a ground state problem, can be extended to open quantum systems. In our formalism, the ground states of an ensemble of non-Hermitian Kitaev–Feynman clock Hamiltonians yield stochastic trajectories, which unravel the evolution of a Lindblad master equation. In this way, one can use the Kitaev–Feynman clock not only to simulate the evolution of a quantum system, but also its interaction with an environment such as a heat bath or measuring apparatus. A simple numerical example of a two-level atom undergoing spontaneous emission is presented and analyzed.en-USmathematical physicsquantum computationopen quantum systemsJournal Article2016-11-1810.1039/C5SC03234B