Continuous quantum measurement for general Gaussian unravelings can exist

Abstract

Quantum measurements and the associated state changes are properly described in the language of instruments. We investigate the properties of a time continuous family of instruments associated with the recently introduced family of general Gaussian non-Markovian stochastic Schrödinger equations. In this Letter we find that when the covariance matrix for the Gaussian noise satisfies a particular $\delta$-function constraint, the measurement interpretation is possible for a class of models with self-adjoint coupling operator. This class contains, for example the spin-boson and quantum Brownian motion models with colored bath correlation functions. Remarkably, due to quantum memory effects the reduced state, in general, does not have a closed form master equation while the unraveling has a time continuous measurement interpretation.

arXiv comment5 pages

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Cited by in corpus (8)

• Non-Markovian Quantum Dynamics in Strongly Coupled Multimode Cavities Conditioned on Continuous Measurement
• Local disclosure of quantum memory in non-Markovian dynamics
• Memory effects in quantum dynamics modelled by quantum renewal processes
• Unraveling-paired dynamical maps can recover the input of quantum channels
• On the unraveling of open quantum dynamics
• Unifying quantum stochastic methods using Wick's theorem on the Keldysh contour
• Purely quantum memory in closed systems observed via imperfect measurements
• Stochastic Schrödinger equation for a homodyne measurement setup of strongly correlated systems