Spinor Matter-Wave Control with Nanosecond Spin-Dependent Kicks

Abstract

Significant aspects of advanced quantum technology today rely on rapid control of atomic matterwaves with hyperfine Raman transitions. Unfortunately, efficient Raman excitations are usually accompanied by uncompensated dynamic phases and coherent spin leakages, preventing accurate and repetitive transfer of recoil momentum to large samples. We provide a systematic study to demonstrate that the limitations can be substantially overcome by dynamically programming an adiabatic pulse sequence. Experimentally, counterpropagating frequency-chirped pulses are programmed on an optical delay line to parallelly drive five Δm=0 hyperfine Raman transitions of ^{85}Rb atoms for spin-dependent kick (SDK) within τ=40 ns, with an f_{SDK}≈97.6% inferred fidelity. Aided by numerical modeling, we demonstrate that by alternating the chirps of successive pulses in a balanced fashion, accumulation of nonadiabatic errors including the spin leakages can be managed, while the dynamic phases can be robustly cancelled. Operating on a phase-stable delay line, the method supports precise, fast, and flexible control of spinor matterwave with efficient Raman excitations.