The project combined expertise of the NSF groups of Jonathan Weinstein (experiment) and Andrei Derevianko (theory) at the University of Nevada, Reno, in collaboration with the ANR group of Daniel Comparat at Laboratoire Aimé Cotton, Université Paris Saclay, CNRS. We propose extending our research towards two new goals: * The use of matrix-isolated alkali atoms as quantum sensors for a fundamental physics measurement: the nuclear anapole moment (NAM) of Cesium-133. * The use of nonclassical superposition states to improve the ensemble spin dephasing time (T2*), and hence potentially improve the statistical sensitivity to the NAM. Despite the incredible success of the Standard Model of Particle Physics, there are still significant unsolved problems. Many of these are related to symmetry violation: Charge, Parity, Time, and combinations thereof. For example, the standard model does not contain enough C and CP violation to explain the matter-antimatter imbalance in our universe, requiring physics beyond the standard model. Within the standard model, there is a long-standing disagreement between atomic and nuclear physics measurements of the parity-violating nuclear anapole moment (NAM). We will study Cesium-133, an atom for which theory can relate atomic measurements to fundamental physics parameters, trapped in a solid noble gas matrix at cryogenic temperatures. Based on our prior work establishing the quantum sensing properties of this system, along with theoretical expectations of how the NAM is enhanced by the matrix, the NAM effect should be readily observable. Our main focus will be investigating the feasibility of this measurement and the potential systematics associated with the solid-state environment. To improve the measurement sensitivity, we will investigate nonclassical superposition states, which we expect will yield orders-of-magnitude improvement in the spin dephasing time (T2*) that limits the sensitivity of quantum sensing measurements. If successful, this would be of importance for quantum sensing in general, quantum sensing for fundamental physics, and shedding light on the NAM puzzle. This project include supporting student and postdoc training in experimental science, enhancing cryogenic atomic physics research infrastructure, promoting diversity in research, and advancing atomic physics applications.