We report the experimental observation, and a theoretical explanation, of collective suppression of linewidths for multiple superconducting qubits coupled to a good cavity. This demonstrates how strong qubit-cavity coupling can significantly modify the dephasing and dissipation processes that might be expected for individual qubits, and can potentially improve coherence times in many-body circuit QED.
@article{arxiv.1302.0665,
title = {Collective Suppression of Linewidths in Circuit QED},
author = {Felix Nissen and Johannes M. Fink and Jonas A. Mlynek and Andreas Wallraff and Jonathan Keeling},
journal= {arXiv preprint arXiv:1302.0665},
year = {2013}
}