TY - THES AU - Athreya Shankar AB - The last three decades have witnessed the rapid rise of technologies based on quantum me-chanical principles. In particular, quantum systems are expected to revolutionize the way we sense and measure properties of our universe. The ongoing transition from fundamental studies of quan-tum systems to a quantum technology revolution is being powered by significant advancements in laser cooling and trapping of atoms, and in the manipulation and readout of quantum degrees of freedom. In this thesis, we contribute to this movement by presenting theoretical ideas of practical relevance, that will enable improved quantum metrology using atom-based platforms. We advance capabilities in three areas of relevance to quantum metrology. First, under the theme of sub-Doppler cooling of large quantums systems, we describe the numerical modeling of a successful experiment for near ground-state cooling of trapped ion crystals with more than 100 ions in a Penning trap. Second, we propose a new readout technique using atom-cavity interactions to continuously and precisely track the relative phase of a spin superposition. Third, we propose a scheme to engineer squeezing on a platform where controllable atom-atom interactions have been hard to achieve, namely atomic Bragg interferometers. In this way, we introduce useful entanglement into a sensing platform traditionally relying on single-atom physics. BT - Department of Physics CY - Boulder DA - 2020-06 N2 - The last three decades have witnessed the rapid rise of technologies based on quantum me-chanical principles. In particular, quantum systems are expected to revolutionize the way we sense and measure properties of our universe. The ongoing transition from fundamental studies of quan-tum systems to a quantum technology revolution is being powered by significant advancements in laser cooling and trapping of atoms, and in the manipulation and readout of quantum degrees of freedom. In this thesis, we contribute to this movement by presenting theoretical ideas of practical relevance, that will enable improved quantum metrology using atom-based platforms. We advance capabilities in three areas of relevance to quantum metrology. First, under the theme of sub-Doppler cooling of large quantums systems, we describe the numerical modeling of a successful experiment for near ground-state cooling of trapped ion crystals with more than 100 ions in a Penning trap. Second, we propose a new readout technique using atom-cavity interactions to continuously and precisely track the relative phase of a spin superposition. Third, we propose a scheme to engineer squeezing on a platform where controllable atom-atom interactions have been hard to achieve, namely atomic Bragg interferometers. In this way, we introduce useful entanglement into a sensing platform traditionally relying on single-atom physics. PB - University of Colorado Boulder PP - Boulder PY - 2020 EP - 183 T2 - Department of Physics TI - Tools for Improved Quantum Metrology on Atomic Platforms VL - Ph.D. ER -