Reducing Microwave Absorption with Chaotic Microwaves

S. Sridhar, Daniel O. Hogenboom, Balam A. Willemsen

E. Doron, Uzy Smilansky, A. Frenkel

Giuliano Benenti, Giulio Casati, Dima L. Shepelyansky

Michał Ławniczak, Szymon Bauch, Oleh Hul +1 more

The influence of direct processes on the cross-correlation function c 12 (ν) and the elastic enhancement factor W S , β was studied experimentally using microwave networks in the presence of absorption. Microwave networks simulate quantum graphs with and without time-reversal symmetry. Direct processes exist because, for example, of non-perfect coupling between a studied system and a measuring device. We show that direct processes strongly influence the cross-correlation function c 12 (ν) in contrast to the enhancement factor W S , β , which is not sensitive to these processes. It makes the enhancement factor W S , β an important measure of the chaoticity of a quantum system.

Bang‐Pin Hou, Shun-Jin Wang, W L Yu +1 more

We consider the one- and two-photon absorption spectra of a four-level Y-type atom with the two highest lying levels driven by a microwave field. We found that in the one-photon absorption case, the microwave field can lead to the probe gain, and the absorption and gain spectral structures depend strongly on the microwave field amplitude. For the two-photon absorption case, the strong microwave field can enhance the absorption. When the microwave field amplitude is reduced to a certain value, the single absorption peak in the two-photon spectrum changes into a structure of two-peak structure with different magnitudes. Moreover, the one- and two-photon absorption spectra can be modulated by the phase of the microwave field which produces a closed-loop configuration. Finally, we use the analytic solutions in terms of dressed-state basis to explain the results from our numerical calculation.