Quantum spin dynamics

Robert Wieser

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arXiv · 1410.6383

Quantum spin dynamics

Robert Wieser

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Abstract

The classical Landau-Lifshitz equation has been derived from quantum mechanics. Starting point is the assumption of a non-Hermitian Hamilton operator to take the energy dissipation into account. The corresponding quantum mechanical time dependent Schrödinger, Liouville and Heisenberg equation have been described and the similarities and differences between classical and quantum mechanical spin dynamics have been discussed. Furthermore, a time dependent Schrödinger equation corresponding to the classical Landau-Lifshitz-Gilbert equation and two ways to include temperature into the quantum mechanical spin dynamics have been proposed.

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Robert Wieser. 2014-10-23. Quantum spin dynamics. https://arxiv.org/abs/1410.6383

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