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Nonequilibrium Extension of the Landau-Lifshitz-Gilbert Equation for Magnetic Systems

Jeongwon Ho·B. C. Choi·F. C. Khanna·Sang Pyo Kim
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Abstract

Using the invariant operator method for an effective Hamiltonian including the radiation-spin interaction, we describe the quantum theory for magnetization dynamics when the spin system evolves nonadiabatically and out of equilibrium, $d \hatρ/dt \neq 0$. It is shown that the vector parameter of the invariant operator and the magnetization defined with respect to the density operator, both satisfying the quantum Liouville equation, still obey the Landau-Lifshitz-Gilbert equation.

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Jeongwon Ho, B. C. Choi, F. C. Khanna, Sang Pyo Kim. 2004-05-26. Nonequilibrium Extension of the Landau-Lifshitz-Gilbert Equation for Magnetic Systems. https://arxiv.org/abs/cond-mat/0405599

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