Complex WKB Method for 3-Level Scattering Systems
نویسنده
چکیده
In this note, recent developements of the Complex WKB method allowing to compute the S-matrix naturally associated with a singularly perturbed three-dimensional system of linear diierential equations without turning point on the real axis are reviewed. It is shown that for a fairly large class of examples, the Complex WKB method gives results far better than what is proven under generic circumstances. In particular, we show how to compute asymptotically all exponentially small oo-diagonal elements of the corresponding S-matrix.
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