Phase-locked, low-noise, frequency agile titanium:: sapphire lasers for simultaneous atom interferometers

We demonstrate a laser system consisting of a > 1.6 W titanium: sapphire. laser that is phase locked to another free-running titanium: sapphire laser at a wavelength of 852 nm with a phase noise of -138 dBc/Hz at 1 MHz from the carrier, using an intracavity electro-optic phase modulator. The residual phase variance is 2.5 X 10(-8) rad(2) integrated from 1 Hz to 10 kHz. This system can phase-continuously change the offset frequency within 200 ns with frequency steps up to 4 MHz. Simultaneous atom interferometers can make full use of this ultralow phase noise in differential measurements, where influences from the vibration of optics are greatly suppressed in common mode. (c) 2006 Optical Society of America.