Enhanced nonlinear optical response of InP(100) membranes

Abstract

The nonlinear optical response of porous InP͑100͒ membranes was examined and compared to that of bulk crystalline ͑100͒-oriented InP. Measurements of optical rectification and optical second-harmonic generation have been carried out in reflection under excitation by 120 fs, 800 nm Ti:Sapphire laser beam pulses. A significant enhancement in both the radiated terahertz field and second-harmonic radiation from the porous InP͑100͒ surface, relative to the bulk InP͑100͒ surface, was observed. Terahertz field polarization measurements indicate that the enhancement is primarily on the component of the radiated field related to optical rectification as opposed to photocarrier-related effects. It is suggested that the enhanced nonlinear optical response is related to strong enhancements of the local field within the porous network.

Heavy noble gas (Kr, Xe) irradiated (111) InP nanoporous honeycomb membranes with enhanced ultrafast all-optical terahertz emission

“…2 ͑Conversely, an absence of magnetic field dependence and nonsaturation with excitation fluence, as exemplified by GaBiAs, 3 rule out the influence of TC.͒ Porous membranes on ͑100͒ InP surfaces give an enhanced NLO response for both second-harmonic and terahertz generation, related to optical rectification ͑OR͒ rather than to TC effects, and attributed to strong local fields in the porous network. 4 Similar enhancements to the terahertz emission in porous samples relative to the bulk precursors have been observed for ͑111͒ InP. 5 Measurements and modeling on charge carriers in porous InP membranes indicate a lower density and lower mobility but much longer recombination lifetime than for bulk InP, attributed to upward bandbending at the pore surfaces.…”

Experimental study of terahertz emission from ZnSe and ZnTe nanostructures

“…It has been recently reported that the THz emission from InP irradiated with 800nm femtosecond laser pulses can be enhanced by introducing a porous surface [13], [14] . Moreover, Gregor also reported metal grating on the semiconductor surface can produce THz radiation based on plasma oscillation [15], [16] .…”

Terahertz Emitters, Detectors and Sensors: Current Status and Future Prospects

“…This could be eliminated by placing nonlinear crystal in hollow metallic waveguide structure . The conversion efficiency in optical rectification depends primarily on the material nonlinear coefficient and the phase-matching conditions and various schemes for power enhancement have been reported [Radhanpura et al, 2010;Bugay & Sazonov, 2010;He et al, 2008;Reid et al, 2008].…”