Nonadiabatic transitions in a two-level system

Yōsuke Kayanuma

博幸 中山

P. R. Berman

Vladimir V. Likhanskii

Expressions are obtained for the probability of a nonadiabatic transition between two degenerate levels under the action of laser radiation with a continuously variable resonance frequency. It is shown that this problem reduces to the solution of the Landau–Zener problem for eigenvectors of the matrix of a transition between two degenerate levels.

V. A. Bazylev, Nick K. Zhevago, M. I. Chibisov

Keiji Saito, Yōsuke Kayanuma

Dissipative effects on the nonadiabatic transition for the two- and three-level systems are studied. When the system is affected by a strong dissipation through the diabatic states, the exact transition probability is enumerated making use of the effective master equation. In the two-level system, we consider the case where the external field is swept from not only a negative large value but also from the resonant field, and the exact transition probabilities in these cases are derived. The transition probabilities are derived for the three-level system where the three diabatic states form only one avoided-level crossing point. These probabilities are compared with that in the pure quantum case obtained by Carroll and Hioe.