Subpicosecond, freely propagating electromagnetic pulse generation and detection using GaAs:As epilayers
نویسندگان
چکیده
Using GaAs epilayers with arsenic precipitates (GaAs:As) as the photoconductive material in a broad-band optoelectronic terahertz beam system, we have generated and detected freely propagating, subpicosecond electromagnetic pulses. The receiver signal gave a measured integrated pulse width of 0.71 ps. Fast photoconductive rise times have been achieved which are characteristic of good mobility GaAs. In addition, the material exhibits a short “effective” carrier lifetime of several ps due to the embedded, closely spaced (about 20 nm) arsenic precipitates.
منابع مشابه
Detection of freely propagating terahertz radiation by use of optical second-harmonic generation.
We report the application of electric-field-induced optical second-harmonic generation as a new technique for measuring the field of freely propagating terahertz radiation. Using silicon as the nonlinear medium, we demonstrate subpicosecond time resolution and a sampling signal that varies linearly with the terahertz electric field. This approach, which is attractive for centrosymmetric media, ...
متن کاملSubpicosecond-pulse generation through cross-phase-modulation-induced modulational instability in optical fibers.
We report subpicosecond-pulse generation at 1.319 microm in a single-mode optical fiber by modulational instability induced through cross-phase modulation by 1.06-microm pulses propagating in the normal dispersion regime. Pulse-repetition rates approaching 300 GHz were achieved.
متن کاملElectro-optic detection of femtosecond electromagnetic pulses by use of poled polymers.
We report the generation and coherent detection of freely propagating ultrashort baseband electromagnetic pulses. Using optical rectification in ?110? GaAs for wideband emission and electro-optic sampling in a poled polymer for wideband detection, we demonstrate spectral sensitivity that extends from the far infrared (lambda~100 mum) to ~33 THz(lambda = 9 mum) . Over a band of nearly 20 THz, a ...
متن کاملEfficient generation of 380 fs pulses of Tliz radiati’on by ultrafast laser pulse excitation of a biased metal-semiconductor interface
We have demonstrated a new method of generating pulses of freely propagating THz electromagnetic radiation. The resulting 380 fs pulses are the shortest directly measured THz pulses in free space to date and are more powerful than those generated by Hertzian dipoles or by resonant dipole antennas. Temporal features as short as 190 fs were observed on these THz radiation pulses and thereby, illu...
متن کاملشبیهسازی ذرهای شتاب دادن الکترونها در پلاسمای کم چگال
One of the interesting Laser-Plasma phenomena, when the laser power is high and ultra intense, is the generation of large amplitude plasma waves (Wakefield) and electron acceleration. An intense electromagnetic laser pulse can create plasma oscillations through the action of the nonlinear pondermotive force. electrons trapped in the wake can be accelerated to high energies, more than 1 TW. Of t...
متن کامل