skip to main content

Title: Improvement in thermal barriers to intense terahertz generation from photoconductive antennas

We study the generation of free-space terahertz (THz) pulses at low THz frequencies using 6H-SiC and 4H-SiC photoconductive antennas. We investigate the dependence of the THz electric field radiated from the biased SiC emitters on the applied bias field and on the incident optical fluence. In this work, bias fields as high as 32 kV/cm, and optical fluences up to 2.5 mJ/cm{sup 2} (for the 400 nm laser), and 7.5 mJ/cm{sup 2} (for the 800 nm laser) were used. THz generation with back- and front-side illumination of the antennas is also examined. It is found that the SiC antenna, when illuminated from the backside, generates higher THz electric fields. The performance of 6H-SiC and ZnSe photoconductive antennas are compared. We show that, taking advantage of the superior thermal properties of SiC compare with ZnSe, the THz output power generated with the 6H-SiC photoconductive antenna under optimum conditions is 2.3 times larger that with a ZnSe photoconductive antenna.
Authors:
 [1] ;  [2] ;  [3] ;  [4] ;  [1]
  1. INRS-EMT, Advanced Laser Light Source, Université du Québec, Varennes, Québec J3X 1S2 (Canada)
  2. (Canada)
  3. Axis Photonique Inc., Varennes, Québec J3X 1S2 (Canada)
  4. Department of Physics, University of Northern British Columbia, Prince George, British Colombia V2N 4Z9 (Canada)
Publication Date:
OSTI Identifier:
22308510
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTENNAS; ELECTRIC FIELDS; ILLUMINANCE; LASER RADIATION; PHOTOCONDUCTIVITY; PULSES; SILICON CARBIDES; THERMAL BARRIERS; THERMODYNAMIC PROPERTIES; THZ RANGE; ZINC SELENIDES