Title :
Mapping the distribution of photo-currents responsible for generation of terahertz pulses at semiconductor surfaces
Author :
Mueckstein, Raimund ; Hatem, Osama ; Natrella, Michele ; Freeman, Joshua R. ; Graham, Chris S. ; Renaud, Cyril C. ; Seeds, Alwyn J. ; Linfield, Edmund H. ; Davies, A. Giles ; Cannard, Paul J. ; Robertson, Mike J. ; Moodie, Dave G. ; Mitrofanov, Oleg
Author_Institution :
Univ. Coll. London, London, UK
Abstract :
Photo-excited charge carriers at semiconductor surfaces generate pulses of terahertz (THz) radiation. By mapping the spatial distribution of the THz radiation in the near-field and the angular emission pattern in the far-field, we link the THz generation process to the photo-current direction. We find that inplane carrier dynamics play an important role and can even be the dominant source of THz radiation.
Keywords :
photoconductivity; photoemission; angular emission pattern; inplane carrier dynamics; photocurrent direction; photocurrent responsible distribution; photoexcited charge carriers; semiconductor surfaces; spatial distribution; terahertz pulses generation; Apertures; Detectors; Optical pulses; Optical surface waves; Probes; Semiconductor device measurement; Surface treatment;
Conference_Titel :
Infrared, Millimeter, and Terahertz waves (IRMMW-THz), 2014 39th International Conference on
Conference_Location :
Tucson, AZ
DOI :
10.1109/IRMMW-THz.2014.6956034
