Pulse Schemes for Robust Atomic Fountain Interferometry

Mark A. Kasevich

Michael H. Goerz, Mark A. Kasevich, Vladimir S. Malinovsky

The robustness of an atomic fountain interferometer with respect to variations in the initial velocity of the atoms and deviations from the optimal pulse amplitude is examined. We numerically simulate the dynamics of an interferometer in momentum space with a maximum separation of 20ℏk and map out the expected signal contrast depending on the variance of the initial velocity distribution and the value of the laser field amplitude. We show that an excitation scheme based on rapid adiabatic passage significantly enhances the expected signal contrast, compared to the commonly used scheme consisting of a series of π/2 and π pulses. We demonstrate further substantial increase of the robustness by using optimal control theory to identify splitting and swapping pulses that perform well on an ensemble average of pulse amplitudes and velocities. Our results demonstrate the ability of optimal control to significantly enhance future implementations of atomic fountain interferometry.

Brenton C. Young, Mark A. Kasevich, Steven Chu

Michael H. Goerz, Mark A. Kasevich, Vladimir S. Malinovsky

We present an analysis of the robustness of existing analytic schemes for the implementation of an atomic fountain interferometer, and develop concepts for improving this robustness through the use of optimal control theory. For an interferometer operating in the Raman regime, we consider an implementation that manipulates the atomic momentum states with a series of Rabi pulses, and analyze how robust the population dynamics are with respect to variations in the effective pulse amplitude seen by the atoms in the atomic clouds, and variations in the initial velocity of the atoms relative to the rest frame. We then show that using rapid adiabatic passage to implement momentum transfer can significantly improve this robustness. Finally, we formulate the most general control conditions for an atomic fountain interferometer and design a functional that can be used for an ensemble optimization over the robustness landscape. We show preliminary results of optimizing the system using Krotov's method, suggesting that optimal control may be able to significantly enhance the robustness of atom interferometers.

Vladimir S. Malinovsky, Michael H. Goerz, Paul D. Kunz +1 more

We apply optimal control theory to design laser pulse sequences implementing the mirrors and beamsplitters of an atomic fountain interferometer. The goal is to enhance the fidelity and the robustness of the interferometer.

David L. Butts, Krish Kotru, Joseph M. Kinast +2 more