Direct processes in chaotic microwave cavities in the presence of absorption.
We quantify the presence of direct processes in the S matrix of chaotic microwave cavities with absorption in the one-channel case. To this end the full distribution P(S)(S) of the S matrix, i.e., S=sqrt[R]e(itheta), is studied in cavities with time-reversal symmetry for different antenna coupling strengths T(a) or direct processes. The experimental results are compared with random-matrix calculations and with numerical simulations including absorption. The theoretical result is a generalization of the Poisson kernel. The experimental and the numerical distributions are in excellent agreement with theoretical predictions for all cases.
Kuhl
U
U
Fachbereich Physik, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg, Germany.
Martínez-Mares
M
M
Méndez-Sánchez
R A
RA
Stöckmann
H-J
HJ