Solid-state carrier-envelope-phase noise measurements with intrinsically balanced detection

We use interference between single- and two-photon photocurrent generation pathways in a semiconductor to measure the out-of-loop carrier-envelope-phase noise of a stabilized Ti:sapphire modelocked laser. This solid-state measurement technique exhibits no significant amplitude/phase coupling, adds no measurable phase noise compared to the standard self-referencing technique, and requires few optical components. The method features a built-in balanced detection mechanism that is particularly appealing for dc carrier-envelope-phase measurements.