Landau-Zener problem for energies close to potential crossing points
V. A. Benderskii+*, E. V. Vetoshkin+, E. I. Kats
+Institute of Problems of Chemical Physics RAS, 142432 Chernogolovka, Moscow Reg., Russia and Laue-Langevin Institute, F-38042, Grenoble, France *L. D. Landau Institute for Theoretical Physics RAS, 117334 Moscow, Russia
PACS: 05.45.-a, 31.50.Gh, 72.10.-d
Abstract
We examine one overlooked in previous investigations
aspect of well - known Landau - Zener (LZ) problem, namely, the behavior
in the intermediate, i.e. close to a crossing point, energy region, when all
four LZ states are coupled and should be taken into account. We calculate
the 4 × 4 connection matrix in this intermediate energy region,
possessing the same block structure as the known
connection matrices for the tunneling and in the over-barrier regions of the
energy, and continously matching those in the corresponding energy regions.
Applications of the results may concern the various systems of
physics, chemistry or biology, ranging from
molecular magnets and glasses to Bose condensed atomic gases.
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