Low-Disorder Microwave Cavity Lattices for Quantum Simulation with   Photons
  We assess experimentally the suitability of coupled transmission line resonators for studies of quantum phase transitions of light. We have measured devices with low photon hopping rates t/2pi = 0.8MHz to quantify disorder in individual cavity frequencies. The observed disorder is consistent with small imperfections in fabrication. We studied the dependence of the disorder on transmission line geometry and used our results to fabricate devices with disorder less than two parts in 10^4. The normal mode spectrum of devices with a high photon hopping rate t/2pi = 31MHz shows little effect of disorder, rendering resonator arrays a good backbone for the study of condensed matter physics with photons. 
Devin L. Underwood, Will E. Shanks, Jens Koch, Andrew A. Houck
quant-ph cond-mat.mes-hall