Second-harmonic generation from silicon nanocrystals embedded in SiO/sub 2/

Summary form only given. Si nanocrystals (ncs) embedded in SiO/sub 2/ are an essential ingredient of a new class of flash memory devices, and show promise as a nonlinear optical material for photonic device applications. We report an optical second-harmonic generation (SHG) study of nc-Si/SiO/sub 2/ nanocomposites. The results show that SHG from nc-Si/SiO/sub 2/ is sensitive to Si/SiO/sub 2/ electronic interface states and to electrostatic charging of the Si ncs, both essential features in their role in electronic device operation. SHG is also sensitive to transverse gradients in nc density, an essential feature in the design of photonic structures. Thus SHG uniquely characterizes materials and devices based on nc-Si/SiO/sub 2/.