Hybrid quantum-classical simulation of quantum speed limits in open quantum systems
arXiv:1812.05779 · doi:10.1088/1751-8121/ab15eb
Abstract
The quantum speed limit (QSL) provides a fundamental upper bound on the speed of quantum evolution, but its evaluation in generic open quantum systems still presents a formidable computational challenge. Herein, we introduce a hybrid quantum-classical method for computing QSL times in multi-level open quantum systems. The method is based on a mixed Wigner-Heisenberg representation of the composite quantum dynamics, in which the open subsystem of interest is treated quantum mechanically and the bath is treated in a classical-like fashion. By solving a set of coupled first-order deterministic differential equations for the quantum and classical degrees of freedom, one can compute the QSL time. To demonstrate the utility of the method, we study the unbiased spin-boson model and provide a detailed analysis of the effect of the subsystem-bath coupling strength and bath temperature on the QSL time. In particular, we find a turnover of the QSL time in the strong coupling regime, which is indicative of a speed-up in the quantum evolution. We also apply the method to the Fenna- Matthews-Olson complex model and identify a potential connection between the QSL time and the efficiency of the excitation energy transfer at different temperatures.
12 pages, 5 figures, comments are welcome
References in corpus (14)
- Quantum speed limit for physical processes
- Quantum speed limits in open system dynamics
- Generalized Clausius inequality for nonequilibrium quantum processes
- Environment assisted speed-up of the field evolution in cavity QED
- Kind of entanglement that speeds up quantum evolution
- Quantum-speed-limit time for multiqubit open systems
- Quantum Speed Limit Bounds in an Open Quantum Evolution
- Comment on "Geometric derivation of the quantum speed limit"
- Optimal control of a qubit in an optical cavity
- Entanglement and the Lower Bounds on the Speed of Quantum Evolution
- High-Speed Driving of a Two-Level System
- An improved bound for quantum speed limit time in open quantum systems by introducing an alternative fidelity
- Statistical ensembles in Hamiltonian formulation of hybrid quantum-classical systems
- Ehrenfest principle and unitary dynamics of quantum-classical systems with general potential interaction