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Complete time-dependent treatment of a three-level system

A. R. P. Rau·Weichang Zhao
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Abstract

Both unitary evolution and the effects of dissipation and decoherence for a general three-level system are of widespread interest in quantum optics, molecular physics, and elsewhere. A previous paper presented a technique for solving the time-dependent operator equations involved but under certain restrictive conditions. We now extend our results to a general three-level system with arbitrary time-dependent Hamiltonians and Lindblad operators. Analytical handling of the SU(3) algebra of the eight operators involved leaves behind a set of coupled first-order differential equations for classical functions. Solution of this set gives a complete solution of the quantum problem, without having to invoke rotating-wave or other approximations. Numerical illustrations are given.

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A. R. P. Rau, Weichang Zhao. 2005-02-17. Complete time-dependent treatment of a three-level system. https://doi.org/10.1103/physreva.71.063822

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