Optical characterization of novel terahertz emitters

Bulk (111) and (100) InP wafers and nanoporous membranes have been studied using free space time-domain spectroscopy. The nonlinear optical response is shown to be dependent on heavy ion (Kr
⁺¹⁵
, Xe
⁺²³
) dose, crystallographic orientation and subsequent pore formation whereby optical techniques are employed for the purpose of surface characterization.