Microwave photons in LC circuits can also be used to detect and control micromechanical oscillators, macroscopic objects that within this framework can be prepared in quantum states of motion and whose displacement can be detection with precision only limited by quantum mechanical uncertainty. Our main research direction here is to continue the development of the most recent platform addition to the family of optomechanical devices – flux-mediated or SQUID optomechanics. In flux-mediated optomechanics (FMOM), a mechanical beam is embedded in a SQUID loop, which forms a magnetic-flux tunable inductance within an LC circuit. This approach has been demonstrated to allow for much larger coupling rates than conventional devices. Our main goal with FMOM is to develop a device which can reach for the first time the optomechanical single-photon regime. In addition, we are investigating possibilities to realize novel interaction and control schemes with this platform using the Kerr nonlinearity of the SQUID circuit and multi-SQUID devices.

Funded by the German Research Foundation (DFG) via grant no. BO 6068/1-2 (Daniel Bothner) and by the Vector Foundation.

D. Bothner*, I. C. Rodrigues*, and G. A. Steele, Communications Physics 5, 33 (2022)
I. C. Rodrigues*, D. Bothner*, and G. A. Steele, Nature Communications 10, 5359 (2019)