Ultra-sensitive all-optical sampling at 1.5 µmusingwaveguide two-photon absorption

Abstract
Ultra-sensitive all-optical sampling at 1.5 µm using two-photon-absorption in a commercial 1.3 µm quantum-well semiconductor laser has been demonstrated. Using only direct detection of the unamplified two photon absorption photocurrent, a temporal resolution of ~2 ps and a sensitivity of less than 2 mW2 have been achieved.