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Distribution of the S-matrix in chaotic microwave cavities with direct processes and absorption

U. Kuhl·M. Martinez-Mares·R. A. Mendez-Sanchez·H. -J. Stoeckmann
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Abstract

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^{iθ}, 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 based on the Heidelberg approach including absorption. The theoretical result is a generalization of the Poisson kernel. The experimental and the numerical distributions are in excellent agreement with random-matrix predictions for all cases.

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U. Kuhl, M. Martinez-Mares, R. A. Mendez-Sanchez, H. -J. Stoeckmann. 2004-07-08. Distribution of the S-matrix in chaotic microwave cavities with direct processes and absorption. https://doi.org/10.1103/physrevlett.94.144101

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