Abstract:I will describe the realization of quantum sensors based on two material platforms: alkali atoms such as rubidium, and spin defects in diamond. These platforms have complementary properties that make each uniquely advantageous for certain sensing applications, as well as challenges that currently limit their sensing performance and functionality. I will discuss engineering approaches to miniaturize and improve the performance of quantum sensors, including photonic-integration of atomic magnetometers, improving light-matter interactions with solid-state spin defects, and stabilization of near-surface quantum emitters through surface treatments.