Probing Polar and Dielectric Materials via Impurity Qubit Relaxometry*

A qubit sensor with an electric dipole moment acquires an additional contribution to its relaxation rate when it is placed in the vicinity of a polar or dielectric material, as a consequence of electric noise arising from polarization fluctuations in the sample. In this talk, we characterize this relaxation rate as a function of experimentally tunable parameters such as sample-probe distance, probe-frequency, and temperature, and demonstrate that it offers a novel window into probing dielectric properties of insulating materials over a wide range of length-scales and frequency-scales. We establish the feasibility of our proposal with a specific qubit of choice and illustrate its ability to probe questions ranging from collective modes in long-range interacting systems, to phase transitions and disorder-dominated phenomena in relaxor ferroelectrics. Our proposal paves the way for a novel table-top probe of dielectric and polar materials, in a parameter regime complementary to existing tools and techniques.