The dragging effect in Ag/Pd nanocomposite film: generation of bipolar pulses

Characteristic features of the phenomenon of longitudinal photocurrent generation in Ag/Pd nanocomposite films under the obliquely incident nanosecond pulsed laser irradiation with wavelengths in the 1350–4000 nm range have been studied for the first time. Films of 20-$\mu$m thickness consisting of nanocrystals of Ag–Pd solid solution and palladium oxide (PdO) were obtained using a thick-film technology. The influence of radiation wavelength on photocurrent pulses has been studied for $s$- and $p$-polarized laser pumping. It is established that the photocurrent pulses generated by $s$-polarized pumping in the 1350–4000 nm wavelength range are monopolar, while $p$-polarized pumping can generate both mono- and bipolar pulses depending on the wavelength. The obtained results are explained by simultaneous generation of photocurrent due to the dragging effect and the surface photogalvanic effect.