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Light-pulse atom interferometry based on Bragg diffraction has become a versatile tool for high-precision measurements and its shortcomings and imperfections have been studied in various aspects. In this thesis we provide a comprehensive numerical study combining the main imperfection effects of first-order single (SBD) and double Bragg diffraction (DBD) and its implications to the measurement signal: higher-order diffraction loss, velocity selectivity, diffraction phases and implications of finite pulse durations with gravitational acceleration. We find that a Doppler detuning corresponding to $10\%$ of the recoil momentum is necessary to differentiate between SBD and DBD in a retro-reflective geometry which is typically the case in space setups. Moreover, DBD is fundamentally limited to narrow (ultra)cold ensembles. Furthermore, we develop a path-based interferometer formalism and apply it to a Mach-Zehnder (Kasevich-Chu) geometry. Here, imperfection effects give rise to spurious interferometer paths which lead to a phase offset between the signals of the outer ports in DBD in the context of gravimetry. Also, the spurious central path leads to beating effects due to three-path interference and acts as a quasi-incoherent background. However, a simple addition of the signals of the outer exit ports leads to an effective port insensitive to these imperfections. Finally, we employ thermal states for atom interferometry. Although they exhibit a worse contrast than pure states, due to their higher atom number they show a better phase sensitivity in the quasi-Bragg regime and pose a competitive input source. |
