Modelling of sub-wavelength THz sources as Gaussian apertures.
Summary of "Modelling of sub-wavelength THz sources as Gaussian apertures."
The THz emission point on a nonlinear electro-optical crystal for generating broadband THz radiation is modeled as a radiating Gaussian aperture. With the wavelengths of the infrared pump beam being much smaller than the wavelength components of the generated THz pulse, a THz sub-wavelength radiating aperture with Gaussian profile is effectively created. This paper comprehensively investigates Gaussian apertures in focused THz radiation generation in electro-optical crystals and illustrates the breakdown of the paraxial approximation at low THz frequencies. The findings show that the shape of the radiation pattern causes a reduction in detectable THz radiation and hence contributes significantly to low signal-to-noise ratio in THz radiation generation. Whilst we have demonstrated the findings on optical rectification in this paper, the model may apply without a loss of generality to other types of apertures sources in THz radiation generation.
Affiliation
Journal Details
This article was published in the following journal.
Name: Optics express
ISSN: 1094-4087
Pages: 17672-83
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20721154
- DOI: http://dx.doi.org/
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