Silicon-nanoparticle-based broadband optical modulators for solid-state lasers.

Abstract

Motivated by the tremendous success of carbon nanomaterials in acting as optical nonlinear modulators, in this Letter, the optical nonlinearity of their counterpart, silicon nanoparticles (SiNPs), is investigated. For the first time, to the best of our knowledge, the nonlinear optical property of SiNPs in 1μm and 2μm wavelength bands is observed. Its practical modulation performance is investigated by employing SiNPs as a saturable absorber (SA) in pulsed lasers, and the fabrication process, surface morphology, and linear and nonlinear optical response properties of the prepared SiNPs-SA are presented. Based on the SiNPs-SA, the formed Q-switched Nd:LuAG laser can generate laser pulses with the shortest duration of 490ns at ∼1 μm and ∼2 μm laser pulses with the shortest duration of 453ns are delivered from a Q-switched Tm:YAP laser, which shows that the SiNPs can be employed as a promising broadband SA for near- and mid-infrared spectral regions.