Multiple lobes in the far-field distribution of terahertz quantum-cascade lasers due to self-interference

Journal Article · Wed Jun 15 00:00:00 EDT 2016 · AIP Advances

DOI:https://doi.org/10.1063/1.4953596· OSTI ID:22611530

Wienold, M.; Schrottke, L.; Grahn, H. T. ^[1]

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1. Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5–7, 10117 Berlin (Germany)

The far-field distribution of the emission intensity of terahertz (THz) quantum-cascade lasers (QCLs) frequently exhibits multiple lobes instead of a single-lobed Gaussian distribution. We show that such multiple lobes can result from self-interference related to the typically large beam divergence of THz QCLs and the presence of an inevitable cryogenic operation environment including optical windows. We develop a quantitative model to reproduce the multiple lobes. We also demonstrate how a single-lobed far-field distribution can be achieved.

• OSTI ID: 22611530
• Journal Information: AIP Advances, Vol. 6, Issue 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BEAMS
DISTRIBUTION
EMISSION
GAUSS FUNCTION
INTERFERENCE
LASERS
OPACITY
OPERATION
THZ RANGE