Achim Marx

TL;DR: In this article, it was shown that the Jaynes-cummings model breaks down in the regime of ultrastrong coupling between light and matter, and that higher-order processes are possible.

TL;DR: The observation of strong coupling between the exchange-coupled spins in a gallium-doped yttrium iron garnet and a superconducting coplanar microwave resonator made from Nb demonstrates that exchange-Coupled systems are suitable for cavity quantum electrodynamics experiments, while allowing high integration densities due to their spin densities of the order of one Bohr magneton per atom.

TL;DR: In this paper, the authors demonstrate frequency-degenerate entanglement between continuous-variable quantum microwaves propagating along two spatially separated paths using a microwave beam splitter.

TL;DR: In this paper, a two-resonator circuit with two on-chip microwave resonators coupled to one superconducting qubit is considered, where the qubit can function as a quantum switch between the two resonators, which are assumed to be originally independent.