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International Journal of Quantum Chemistry

Usage de l'algebre de lie su(n) dans l'etude des systems à n etats. VI. Equations linéaires d'evolution positive

A. Van Groenendael

Published Jul 1, 1986• 1 citation

Abstract

Abstract The n‐level quantum system density‐operators evolution is not usually given by the Liouville equation, but by a more general one. This equation must keep density‐operators trace, hermiticity, and positiveness. These three conditions restrict the available kinds of evolution equations. In this paper we investigate linear equations for systems without memory effects. By using the first two conditions and the formalism we introduced in earlier papers, the evolution equation takes the form of a first order differential equation concerning the n2 – 1 dimension “coherence‐vector.” The third one is the essential object of this paper. Moreover, we obtain a cononical splitting of this equation into four parts that may be separately studied.

DOI: 10.1002/qua.560300115

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