Optimizing Solid-State Spins in Diamond for Nano- to Millimeter-Scale Magnetic Field Sensing

Abstract

Solid-state defect impurities have established themselves as an impactful research platform providing novel pathways to a broad spectrum of problems in physics, biology, chemistry, geology, medicine and materials science. In this dissertation, we present several achievements to improve the sensing capabilities of nitrogen-vacancy (NV) center spins in diamond. The NV defect stands out among impurities currently being investigated. Its prominence in the field is facilitated by its exceptionally long ground-state spin lifetimes at room temperature, an optical spin polarization and readout mechanism, and its capability to be manipulated via coherent microwaves and static magnetic fields. In the introductory chapter, we review the fundamental aspects of NV research, which encompasses modern applications, processing techniques, and primary sequences for manipulation of the NV spin state. In the second chapter, we describe the spin bath environment surrounding the NV center spins. In chapters three and four, we present two optical methods to extend the NV sensing capabilities to nanometric spatial resolution and to enhance the readout fidelity of NV spin ensembles. Chapters five and six present a detailed study of dephasing and decoherence mechanisms for NV spin ensembles in a bath of paramagnetic nitrogen spins.