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Abstract Ultrafast adiabatic frequency conversion is a powerful method, capable of efficiently and coherently transfering ultrashort pulses between different spectral ranges, e.g. from near-infrared to mid-infrared, visible or ultra-violet. This is highly desirable in research fields that are currently limited by available ultrafast laser sources, e.g. attosecond science, strong-field physics, high-harmonic generation spectroscopy and multidimensional mid-infrared spectroscopy. Over the past decade, adiabatic frequency conversion has substantially evolved. Initially applied to quasi-monochromatic, undepleted pump interactions, it has been generalized to include ultrashort, broadband, fully-nonlinear dynamics. Through significant theoretical development and experimental demonstrations, it has delivered new capabilities and superior performance in terms of bandwidth, efficiency and robustness, as compared to other frequency conversion techniques. This article introduces the concept of adiabatic nonlinear frequency conversion, reviews its theoretical foundations, presents significant milestones and highlights contemporary ultrafast applications that may, or already do, benefit from utilizing this method.
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Back-conversion suppressed parametric frequency conversion for ultrawide bandwidth and ultrahigh efficiency devices
For as widely used a tool as nonlinear optical frequency conversion is for both science and industry, it remains widely limited in eciency and bandwidth (and ultimately also in cost) due to the fundamental problem of backconversion in the nonlinear evolution dynamics. This review paper covers new developments and capabilities in frequency conversion devices, including optical up- and down-converters and ampli ers, based on nonlinear evolution dynamics in which back-conversion is suppressed. One such approach is adiabatic frequency conversion, in which the dynamics of rapid adiabatic passage replace the regular cyclic conversion evolution in phase-matched sum- and di erence-frequency generation. This approach has enabled devices far surpassing the conventional eciency-bandwidth trade-o . For example, in chirped quasi-phase matched quadratic crystals, microjouleenergy single-cycle mid-infrared pulses were generated with arbitrary pulse shaping capability, presenting a source with unique features for nonlinear spectroscopy and strong- eld physics applications. We review new developments in the use of optical bers as a cubic nonlinear platform for the same concept, utilizing a tapered core diameter or a pressure gradient to allow up- and down-conversion with ultra-wide bandwidth and high eciency. We also review a newly introduced concept for high eciency optical parametric ampli cation, via a novel approach for suppressing back-conversion in optical parametric ampli cation by simultaneously phasematching the idler wave for second harmonic generation. Keywords: Adiabatic wave mixing, ecient optical parametric ampli cation, octave-spanning
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- PAR ID:
- 10146291
- Date Published:
- Journal Name:
- SPIE LASE, 2020, San Francisco, California, United States
- Page Range / eLocation ID:
- 10
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.1117/12.2548361
