Journal article
GHz-bandwidth upconversion detector using a unidirectional ring cavity to reduce multilongitudinal mode pump effects
We demonstrate efficient upconversion of modulated infrared (IR) signals over a wide bandwidth (up to frequencies in excess of 1 GHz) via cavity-enhanced sum-frequency generation (SFG) in a periodically poled LiNbO3. Intensity modulated IR signal is produced by combining beams from two 1547 nm narrow-linewidth lasers in a fiber coupler while tuning their wavelength difference down to 10 pm or less.
The SFG crystal is placed inside an Nd:YVO4 ring cavity that provides 1064 nm circulating pump powers of up to 150 W in unidirectional operation. Measured Fabry-Perot spectrum at 1064 nm confirms the enhanced spectral stability from multiple to single longitudinal mode pumping condition. We describe analytically and demonstrate experimentally the deleterious effects of using a multimode pump to the high-bandwidth RF spectrum of the 630 nm SFG output.
Offering enhanced sensitivity without the need for cooling, the GHz-bandwidth upconverter can readily be extended to the mid-IR (2 - 5 mu m) as an alternative to cooled low-bandgap semiconductor detectors for applications such as high-speed free-space optical communications. (C) 2017 Optical Society of America
Language: | English |
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Year: | 2017 |
Pages: | 14783-14794 |
ISSN: | 10944087 |
Types: | Journal article |
DOI: | 10.1364/OE.25.014783 |
ORCIDs: | Tidemand-Lichtenberg, Peter , Pedersen, Christian , Rodrigo, Peter John and 0000-0001-9787-2195 |