Photoinduced desorption of Xe from porous Si following ultraviolet irradiation: Evidence for a selective and highly effective optical activity

Photoinduced desorption (PID) of Xe from porous silicon (PSi) following UV irradiation has been studied. A nonthermal, morphology, and wavelength dependent phenomenon with more than 3 orders of magnitude enhancement of Xe PID within pores over atoms adsorbed on top of flat surfaces has been recorded, displaying extraordinary large cross sections up to σ_Xe/PSi= 2×10^-15cm2. A long-lived, photoinduced, charge separated silicon-xenon complex is proposed as the precursor for this remarkable photodesorption process.