  We present the development of a laser system for performing single-photon
atom interferometry on the 698 nm clock transition in ultracold Strontium. We
coherently combine the power of two Titanium:Sapphire lasers and demonstrate
chirps of 200 MHz in 2.5 ms while phase-locked to an optical reference.
Moreover, we demonstrate a novel scheme to deliver 4 W pulsed beams to the
atoms via a mode-cleaning optical fiber using active noise cancellation.
