Serrodyne Matterwave Optics

Abstract

Bragg diffraction for atom interferometry conventionally requires two laser frequencies whose difference makes the two-photon transition resonant. We show that this frequency difference can instead be generated by serrodyne modulation, allowing Bragg pulses to be driven with a single-frequency laser. The serrodyne modulation is performed using an acousto-optic modulator driven with a phase-modulated RF drive, and generated kilohertz-scale frequency shifts on top of the AOM carrier frequency. While in general serrodyne modulation generates strong unwanted frequency components, we find conditions so that the Bragg diffraction pulses, and atom interferometers constructed from them, are robust to these imperfections, opening the door to the development of ultra compact, single frequency Bragg diffraction based atom interferometers with serrodyne modulation implemented by a position modulated retroreflection mirror.