Abstract
A broadly tunable THz source is realized via difference frequency generation, in which an enhancement to χ(3) that is obtained via resonant excitation of III–V semiconductor quantum well excitons is utilized. The symmetry of the quantum wells (QWs) is broken by utilizing the built-in electric-field across a p–i–n junction to produce effective χ(2) processes, which are derived from the high χ(3). This χ(2) media exhibits an onset of nonlinear processes at ~4 W cm−2, thereby enabling area (and, hence, power) scaling of the THz emitter. Phase matching is realized laterally through normal incidence excitation. Using two collimated 130 mW continuous wave (CW) semiconductor lasers with ~1-mm beam diameters, we realize monochromatic THz emission that is tunable from 0.75 to 3 THz and demonstrate the possibility that this may span 0.2–6 THz with linewidths of ~20 GHz and efficiencies of ~1 × 10–5, thereby realizing ~800 nW of THz power. Then, transmission spectroscopy of atmospheric features is demonstrated, thereby opening the way for compact, low-cost, swept-wavelength THz spectroscopy.
Original language | English |
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Article number | 29 |
Journal | Light: Science and Applications |
Volume | 8 |
Issue number | 1 |
DOIs | |
Publication status | Published - 13 Mar 2019 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
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Structural and Opto-Electronic Properties of GaAs and InP Based Quantum Dot Lasers
Butler, I. (Author), Hogg, R. (Supervisor), Childs, D. (Supervisor) & Bowman, R. (Supervisor), Dec 2020Student thesis: Doctoral Thesis › Doctor of Philosophy
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