Dynamical tunneling in closed and open microwave cavities

A.R. Bosco de Magalhães, Maria Carolina Nemes

Charles P. Meaney, Hyunchul Nha, T. Duty +1 more

Petr Šeba, I. Rotter, Markus Müller +2 more

Y.-H. Kim, Ulrich Kuhl, H.-J. Stöckmann +1 more

We investigate the signatures of dynamical tunnelling in open quantum dots, by implementing a soft-walled microwave cavity as a novel analogue system. We explore the evidence for dynamical tunnelling by studying the evolution of the wavefunction phase as a function of frequency and show evidence for evanescent coupling to isolated orbits, including the existence of 'dirty' states in the wavefunction that are generated from a degenerate pair of 'clean' states when they are degraded by their tunnelling interaction. Our investigations provide a useful analogue of quantum transport in open quantum dots, and demonstrate the importance of dynamical tunnelling that arises from the mixed classical dynamics that is inherent to these structures.

Laure E. Bruhat, J. J. Viennot, Matthieu Dartiailh +3 more

Microwave cavities are widely used to control closed few-level systems in the context of quantum information processing. Now, they also appear as a powerful probe for quantum tunneling in hybrid nanocircuits.

Pasquale Maddaloni, Marco Bellini, Paolo De Natale

For many contemporary physics experiments, the use of microwave and optical resonators has become a powerful tool for enhancement in detection sensitivities, nonlinear interactions, and quantum dynamics. Most often, the term cavity is used to describe such electromagnetic resonators. This term has been taken over from microwave technology, where resonators really look like closed cavities, whereas optical resonators traditionally have an open kind of setup. That difference in geometry is related to the fact that optical resonators are usually very large compared with the optical wavelength, whereas microwave cavities are often not much longer than a wavelength. As discussed in the course of this book, microwave and optical cavities allow one to extend the interaction length between matter and field, to build up the optical power, to impose a well-defined mode structure on the electromagnetic field, to implement extreme nonlinear optics, and to study manifestly quantum mechanical behavior associated with the modified vacuum structure and/or the large field associated with a single photon confined to a small volume [100].