AgInSe2 nanorods: A semiconducting material for saturable absorber

Abstract

AgIn Se2 nanorods (NRs) with a diameter of 15 nm have been investigated for their nonlinear optical responses by using Z -scan and transient absorption techniques with femtosecond laser pulses of photon energy greater than the band gap. At excitation irradiance of 20 GW cm2, AgIn Se2 NRs reveal saturation in the nonlinear absorption and optical Kerr nonlinearity with a recovery time determined to be a few tens of picoseconds. Such large saturable absorption and Kerr nonlinearity exhibit a third-order susceptibility of 1.2× 10-8 esu and a figure of merit of 0.04 esu cm s-1, making AgIn Se2 NRs a promising candidate for saturable absorption devices. © 2007 American Institute of Physics.