Quantum Sensor for D/H Ratio Measurement in Water in Outer Planets

The study of the ratio of deuterium to hydrogen (D/H) isotopes allows the determination of whether the water originated from comets and asteroids, or it was formed through processes such as solar wind implantation or outgassing from a moonrsquo;s interior. This information can provide insight into the early history and formation of the moon and the inner Solar System, with significant implications for future lunar exploration and the development of sustainable space exploration programs.nbsp;We have designed an innovative quantum sensor for D/H ratio measurement in water using spin centers as a probe for detecting nuclear spins of the isotopes. The proposed sensor indirectly measures the D/H ratio by interrogating shallow spin centers included within the walls of a container using optical and a combination of radio frequency (RF) and microwave (MW) signals. By confining the sample in a small container volume, this proposed sensor limits the effects of diffusion noise and enhances the samplersquo;s polarization without requiring hard to implement techniques such as hyperpolarization, thus providing higher resolution capability using simpler setups. Due to their low-cost and improved size, weight and power consumption, the proposed sensors could cover the growing need for robust sensors with small footprints suitable fornbsp;in-situnbsp;measurements in space missions. The principal Phase II deliverable will be a compact, robust, room-temperature quantum NV-NMR sensor optimized for application to address measurements of D/H ratio in water. This device involves a bottom illumination/detection configuration, adding a microfluidic transparent chamber for optical readout and a coplanar waveguide (CPW) to deliver MW multi-pulse sequences.nbsp; We will characterize device performance, including magnetic-field sensitivity, noise, and power consumption to confirm the devicersquo;s effectiveness for NASA requirements and aligning with device simulations.