Abstract

Since Canham's report that porous silicon (PS) exhibits efficient visible photoluminescence under UV illumination at room temperature [1], extensive investigations addressing porous silicon's pore formation, surface morphology, photo/electroluminescent mechanism(s), and applications are already well reviewed [2-5]. Although much debate still surrounds porous silicon in the aforementioned areas, the viability of porous silicon as an optoelectronic material (e.g. optical switch) is well realized [6]. Thus, the motivation for our efforts is to find a new viable optoelectronic medium, namely a colloidal suspension of porous silicon nanoparticles in some cases microparticles. Colloidal suspensions of gold and polymer composites, possibly due to quantum confinement effects, have yielded large third order nonlinearities of 10^-5 to 10^-8 esu [7].

© 1995 Optical Society of America