Accelerating the search for axionic dark matter with quantum information technology

Several hypothetical origins for dark matter, including the QCD axion, posit the existence of feeble but ever-present source terms in Maxwell’s equations. Because these terms would oscillate at an unknown frequency, searches for this type of dark matter scan a tunable resonant cavity, with spectrally narrow sensitivity, through frequency looking for excess electrical energy in the cavity. Quantum noise now limits the rate at which frequency space can be searched, and for the QCD axion the time required to falsify the benchmark theory is prohibitively long. I will describe how the quantum-limited search rate can be accelerated using technology emerging from the effort to create quantum computers. In particular, I will describe how quantum squeezing of microwave fields increases the bandwidth of the resonant cavities without diminishing their sensitivity.