There is a growing need to adapt quantum sensing techniques for use in fundamental physics experiments, including searches for dark matter, gravitational waves, and the neutrino mass. Quantum-enhanced experiments can achieve better sensitivity than a comparably-sized purely classical experiment. Well-developed techniques like squeezing and photon counting have been deployed in operating dark matter and gravitational wave detectors and demonstrated improved science reach, but do not operate in all frequency bands. In particular, new quantum sensing techniques for electromagnetic signals below ~100MHz would be useful for a range of fundamental physics experiments. In this talk, I will give a brief overview of several experimental efforts I have worked on to achieve sensitivity at or beyond the Standard Quantum Limit (SQL) for these types of signals. I start by discussing my work on DM Radio, an experiment searching for low-mass axion dark matter, and devices I developed that have the potential to enhance its sensitivity beyond the SQL with backaction evading measurements. Next, I'll describe a spin-noise-limited nuclear magnetic resonance (NMR) instrument that I helped develop for CASPEr-E, which also searches for axions. Finally, I'll describe two future research directions based on these foundations. First, I propose to use similar circuits and techniques to augment leading neutrino mass experiments based on Cyclotron Radiation Emission Spectroscopy (CRES). Second, I'll describe how to adapt the quantum-limited NMR instrument to detect electron spins in condensed matter systems, allowing for a qualitatively new method of electron spin resonance (ESR).