Parametrization and optimization of Gaussian non-Markovian unravelings for open quantum dynamics

Abstract

We derive a family of Gaussian non-Markovian stochastic Schrödinger equations for the dynamics of open quantum systems. The different unravelings correspond to different choices of squeezed coherent states, reflecting different measurement schemes on the environment. Consequently, we are able to give a single shot measurement interpretation for the stochastic states and microscopic expressions for the noise correlations of the Gaussian process. By construction, the reduced dynamics of the open system does not depend on the squeezing parameters. They determine the non-hermitian Gaussian correlation, a wide range of which are compatible with the Markov limit. We demonstrate the versatility of our results for quantum information tasks in the non-Markovian regime. In particular, by optimizing the squeezing parameters, we can tailor unravelings for optimal entanglement bounds or for environment-assisted entanglement protection.

5 pages, 1 figure

References in corpus (13)

• Non-Markovian quantum jumps
• Scaling laws for the decay of multiqubit entanglement
• Mapping the optimal route between two quantum states
• Thermodynamical Control by Frequent Quantum Measurements
• High-performance solution of hierarchical equations of motions for studying energy-transfer in light-harvesting complexes
• Controlling entanglement by direct quantum feedback
• Measuring Multipartite Concurrence with a Single Factorizable Observable
• Pure-state quantum trajectories for general non-Markovian systems do not exist
• General Non-Markovian structure of Gaussian Master and Stochastic Schrödinger Equations
• Non-Markovian continuous quantum measurement of retarded observables
• Entanglement dynamics in open two-qubit systems via diffusive quantum trajectories
• Multipartite Entanglement Evolution Under Separable Operations
• Average entanglement dynamics in open two-qubit systems with continuous monitoring

Cited by in corpus (10)

• Rate operator unravelling for open quantum system dynamics
• Convergence guarantees for discrete mode approximations to non-Markovian quantum baths
• Collision model for non-Markovian quantum trajectories
• Stochastic unravellings of non-Markovian completely positive and trace preserving maps
• Memory-induced geometric phase in non-Markovian open systems
• Continuous quantum measurement for general Gaussian unravelings can exist
• Noncommutative phase-space effects in thermal diffusion of Gaussian states
• Quantum speed limit from a quantum-state-diffusion method
• Memory effects in quantum dynamics modelled by quantum renewal processes
• Positivity Preserving non-Markovian Master Equation for Open Quantum System Dynamics: Stochastic Schrödinger Equation Approach