Ultrasharp Crossover from Quantum to Classical Decay in a Quantum Dot Flanked by a Double-Barrier Tunneling Structure

Denis A. Gorokhov; Rava A. da Silveira

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arXiv · cond-mat/0308023

Ultrasharp Crossover from Quantum to Classical Decay in a Quantum Dot Flanked by a Double-Barrier Tunneling Structure

Denis A. Gorokhov·Rava A. da Silveira

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Abstract

The decay of metastable states is dominated by quantum tunneling at low temperatures and by thermal activation at high temperatures. The escape rate of a particle out of a square well is calculated within a semi-classical approximation and exhibits an `ultrasharp' crossover: a kink in the decay rate separates a purely quantum regime at low temperatures from a purely thermal regime at high temperatures. An experimental system -- a quantum dot supplemented by a semiconductor heterostructure -- that may be used to check the prediction, along with necessary experimental conditions, are described.

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Denis A. Gorokhov, Rava A. da Silveira. 2003-08-01. Ultrasharp Crossover from Quantum to Classical Decay in a Quantum Dot Flanked by a Double-Barrier Tunneling Structure. https://arxiv.org/abs/cond-mat/0308023

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