V. A. Benderskii, E. I. Kats, “Nonexponential decay in the quantum dynamics of nanosystems”, Pis'ma v Zh. Èksper. Teoret. Fiz., 2008, Volume 88, Issue 5,Pages <nobr>386

This article is cited in 12 papers

QUANTUM INFORMATION SCIENCE

Nonexponential decay in the quantum dynamics of nanosystems

V. A. Benderskii^a, E. I. Kats^bc

^a Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow region, 142432, Russia
^b Landau Institute for Theoretical Physics, Russian Academy of Sciences, Chernogolovka, Moscow region, 142432, Russia
^c Institut Laue-Langevin, 6 rue J. Horowitz, BP 156, F-38042 Grenoble, Cedex 9, France

Abstract: The quantum dynamical problem is solved for a system coupled to an equidistant-spectrum bath with the energy difference Ω between the neighboring levels n and n + 1 and the coupling matrix elements C _n² = C ²(1 + Δ⁻² n ²)⁻¹ constraining the energy interval comprising the bath states interacting with the system. The evolution in the strong-coupling limit is determined by two parameters, Γ = πC ²/Ω ≫ 1 and α = Γ/Δ. If α ≠ 0, then the decrease in the population in the initial cycle with a period of 2π/Ω is not exponential and the effective rate constant increases with time. The results qualitatively explain the appearance of nonexponential relaxation regimes for a dense-spectrum nanosystem and predict the possibility of the multiple recovery of the initial-state population.

PACS: 03.65.-w, 82.20.-w

Received: 17.07.2008