YQI Talk - Nicholas Rapidis - Stanford University

 

Breakthroughs in quantum science now enable new sensing capabilities for fundamental physics experiments. Searches for dark matter axions provably require sensors operating beyond the standard quantum limit. Such experiments search for a narrowband excess of power in an electromagnetic resonator operating at cryogenic temperatures. Since axions are well motivated across frequencies from kHz to >100 GHz, different quantum sensing modalities are necessary. I will first motivate the techniques used across these frequency ranges. DMRadio-GUT, the ultimate low-frequency axion experiment operating below 10 MHz, will require quantum enhancement through back-action-evading techniques to achieve its required sensitivity. I present recent work on the development of this experiment, as well as ongoing work on DMRadio-50L, which is being commissioned at Stanford University as both an axion search experiment and a quantum-sensor testbed for DMRadio-GUT.