We present the use of grounding airbridge arrays to trim the frequency of microwave coplanar-waveguide (CPW) resonators post fabrication. This method is compatible with the fabrication steps of conventional CPW airbridges and crossovers and increases device yield by allowing compensation of design and fabrication uncertainty with 100MHz range and 10MHz resolution. We showcase two applications in circuit QED. The first is elimination of frequency crowding between resonators intended to readout different transmons by frequency-division multiplexing. The second is frequency matching of readout and Purcell-filter resonator pairs. Combining this matching with transmon frequency trimming by laser annealing reliably achieves fast and high-fidelity readout across 17-transmon quantum processors.
@article{arxiv.2302.10705,
title = {Post-fabrication frequency trimming of coplanar-waveguide resonators in circuit QED quantum processors},
author = {S. Vallés-Sanclemente and S. L. M. van der Meer and M. Finkel and N. Muthusubramanian and M. Beekman and H. Ali and J. F. Marques and C. Zachariadis and H. M. Veen and T. Stavenga and N. Haider and L. DiCarlo},
journal= {arXiv preprint arXiv:2302.10705},
year = {2024}
}