Generating High-Power Bragg Pulses for Atom Interferometry

Achieving lower systematic errors in atom interferometry calls for high-quality optical beams with large areas and therefore large optical powers. To this end, we are building a high-power quasi CW laser system, generating 250-μs pulses with up to 100-Hz repetition rate of light near the 852 nm D2 line of Cesium by amplifying a 500-mW Nd:YAG CW seed to produce up to 10 kW peak power at 1064 nm in 1 J pulses. This is converted to more than 7 kW of peak power at 532 nm using second harmonic generation in LBO. We will use this to pump optical parametric amplification in non-critically phase-matched LBO, seeded by light at 852 nm. This system is designed to deliver more than 1 kW peak power and should allow us to realize higher-order Bragg diffraction in our atomic fountain, a major step towards a higher precision measurement of the fine structure constant.