Dark matter signal enhancement with a superconducting qubit**

The signal from low mass bosonic dark matter, such as axions or hidden photons, in 5-30 GHz regime is vanishing due to the shrinking detector volume. We propose to enhance the signal rate by initializing the microwave cavity in a large n-photon Fock state to stimulate the emission of the dark matter into a photon. We use the non-linearity inherited from a superconducting qubit to create the cavity Fock states and expect to enhance the signal rate by a factor of 10 before being limited by the coherence time of the cavity. We will demonstrate novel quantum control schemes using QM OPX to implement real-time feedback and Hidden Markov Model analysis [1] to improve the experimental protocol and reduce the detector dead-time by a factor of 10.

[1] Dixit et al., Phys. Rev. Lett. 126, 141302 (2021)