Carmo R B do, Aguiar F M de
Universidade Federal de Pernambuco, Departamento de Física, Recife, PE 50670-901, Brazil.
Sci Rep. 2019 Mar 6;9(1):3634. doi: 10.1038/s41598-019-40048-0.
Fluctuations in the one-port scattering and normalized impedance matrices in three polygonal and one chaotic time-reversal invariant microwave billiards are experimentally investigated, in several levels of coupling and absorption, at room temperature and at 77 K. The observed distributions of reflection coefficient, phase of the scattering matrix, resistance and reactance exhibit no fingerprint of a given geometry. At low frequencies, the results are consistent with earlier theoretical models by López, Mello and Seligman and by Zheng, Antonsen and Ott, who independently predicted that the scattering fluctuations might be the same for the Wigner and Poisson level spacing distributions in the lossless cavity. The uniqueness of the observed scattering statistics at higher absorption levels is discussed with respect to inherent limitations posed by the experimental technique.
在室温及77K温度下，针对三种多边形和一种混沌的时间反演不变微波台球，在几个耦合和吸收水平上，对单端口散射以及归一化阻抗矩阵的波动进行了实验研究。所观察到的反射系数、散射矩阵相位、电阻和电抗的分布并未呈现出特定几何形状的特征。在低频时，结果与López、Mello和Seligman以及Zheng、Antonsen和Ott早期的理论模型一致，他们独立预测，在无损腔中，对于维格纳和泊松能级间距分布，散射波动可能是相同的。针对实验技术所带来的固有局限性，讨论了在较高吸收水平下所观察到的散射统计的独特性。
