Quantum Fermi's Golden Rule

Fausto Rossi

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arXiv · quant-ph/0702233

Quantum Fermi's Golden Rule

Fausto Rossi

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Abstract

We shall revisit the conventional adiabatic or Markov approximation, showing its intrinsic failure in describing the proper quantum-mechanical evolution of a generic subsystem interacting with its environment. In particular, we shall show that -contrary to the semiclassical case- the Markov limit does not preserve the positive-definite character of the corresponding density matrix, thus leading to highly non-physical results. To overcome this problem, we shall propose an alternative adiabatic procedure which (i) in the semiclassical limit reduces to the standard Fermi's golden rule, and (ii) describes a genuine Limblad evolution, thus providing a reliable/robust treatment of energy-dissipation and dephasing processes.

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Fausto Rossi. 2007-02-26. Quantum Fermi's Golden Rule. https://arxiv.org/abs/quant-ph/0702233

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