Universal transport properties of open microwave cavities with and without time-reversal symmetry

TL;DR

This study experimentally investigates the universal transport properties of chaotic microwave cavities, examining the effects of time-reversal symmetry breaking and absorption, and confirms theoretical predictions with empirical data.

Contribution

It extends random matrix theory predictions to include absorption effects and provides experimental validation for universal transmission fluctuations in microwave cavities.

Findings

Good agreement between theory and experiment for transmission distributions

Ferrite cylinders effectively break time-reversal symmetry

Absorption strength can be fitted to match theoretical predictions

Abstract

We measure the transmission through asymmetric and reflection-symmetric chaotic microwave cavities in dependence of the number of attached wave guides. Ferrite cylinders are placed inside the cavities to break time-reversal symmetry. The phase-breaking properties of the ferrite and its range of applicability are discussed in detail. Random matrix theory predictions for the distribution of transmission coefficients T and their energy derivative dT/dE are extended to account for absorption. Using the absorption strength as a fitting parameter, we find good agreement between universal transmission fluctuations predicted by theory and the experimental data.