Study Characterizes Length-Dependent Spectral Response of Noncritically Phase-Matched KTP Crystals for SWIR Upconversion Detection
Researchers characterized how crystal length affects the external upconversion spectral response of noncritically phase-matched (NCPM) KTP crystals used in short-wave infrared detection systems. The study measured normalized external responses of crystals ranging from 0.5 to 2.0 mm and found that response profiles evolve from broad to double-peaked as length increases. The findings provide practical guidance for optimizing crystal length selection in SWIR upconversion detection applications.
A new experimental study published on arXiv examines how the physical length of noncritically phase-matched KTP crystals influences their spectral response characteristics for short-wave infrared upconversion detection. Using a calibrated Czerny-Turner monochromator, researchers measured the normalized external responses of three crystal samples (0.5, 1.0, and 2.0 mm) and compared the results against theoretical quantum-efficiency spectra derived from phase-matching models. The analysis revealed that as crystal length increases, the spectral response profile transitions from a broad distribution to a more defined double-peak pattern. The researchers also conducted representative pump-power measurements to evaluate system-level external quantum efficiency. These results offer practical design guidance for engineers selecting appropriate crystal lengths when developing SWIR upconversion detection systems that leverage NCPM KTP crystals' advantages, including large-aperture bulk operation, absence of walk-off effects, and relaxed angular-alignment requirements.
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- arXiv physicsCenter
Length-dependent SWIR upconversion spectral response of noncritically phase-matched KTP crystals
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