Optika Atmosfery i Okeana Journal

Vol. 35, issue 10, article # 12

Ezhov D. M., Lubenko D. M., Mamrashev A. A., Andreev Yu. M. Temperature dependences of the refractive indices of a nonlinear LiB₃O₅ crystal in the THz range. // Optika Atmosfery i Okeana. 2022. V. 35. No. 10. P. 878–880. DOI: 10.15372/AOO20221012 [in Russian].
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Abstract:

Using nonlinear LBO crystals of 30×30×10 mm³ in size, the spectral-temperature dependences of refractive indices in the long-wavelength part of the THz range 0.05–0.5 THz are obtained by means of terahertz time-domain spectroscopy under heating from 20 to 200°C. Intersection of spectral dependences of the refractive index components n_x and n_y at ~84°C is found. The results can be used for selection of types and phase-matching conditions for frequency conversion into long-wavelength part of the THz range, which is prospective for monitoring the gas composition of the atmosphere due to weak influence of the aerosol attenuation.

Keywords:

nonlinear crystal, lithium triborate, LiB3O5, THz range, temperature dependence, refractive index, difference frequency generation, birefringence

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