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Frequency combs with mode spacing of 10–20 GHz are critical for increasingly important applications such as astronomical spectrograph calibration, high-speed dual-comb spectroscopy, and low-noise microwave generation. While electro-optic modulators and microresonators can provide narrowband comb sources at this repetition rate, a significant remaining challenge is a means to produce pulses with sufficient peak power to initiate nonlinear supercontinuum generation spanning hundreds of terahertz (THz) as required for self-referencing. Here, we provide a simple, robust, and universal solution to this problem using off-the-shelf polarization-maintaining amplification and nonlinear fiber components. This fiber-integrated approach for nonlinear temporal compression and supercontinuum generation is demonstrated with a resonant electro-optic frequency comb at 1550 nm. We show how to readily achieve pulses shorter than 60 fs at a repetition rate of 20 GHz. The same technique can be applied to picosecond pulses at 10 GHz to demonstrate temporal compression by 9× and achieve 50 fs pulses with a peak power of 5.5 kW. These compressed pulses enable flat supercontinuum generation spanning more than 600 nm after propagation through multi-segment dispersion-tailored anomalous-dispersion highly nonlinear fibers or tantala waveguides. The same 10 GHz source can readily achieve an octave-spanning spectrum for self-referencing in dispersion-engineered silicon nitride waveguides. This simple all-fiber approach to nonlinear spectral broadening fills a critical gap for transforming any narrowband 10–20 GHz frequency comb into a broadband spectrum for a wide range of applications that benefit from the high pulse rate and require access to the individual comb modes.
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This content will become publicly available on April 11, 2026
Increasing Sensing Spatial Resolution in Soft Robots with Stretchable Optical Networks
A network of stretchable optical waveguides is created and tested under locally applied lateral force and stretching. The network is comprised of urethane waveguides formed into interconnected junctions. These junctions split light pulses sent from a time-of-flight sensor, causing them to travel down different paths throughout the network and are input agnostic. The different split pulses' arrival times and amplitudes can be used to detect these deformations, differentiate between types of deformations and locate which junctions they occurred between.le
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- Award ID(s):
- 1935312
- PAR ID:
- 10657789
- Publisher / Repository:
- IEEE
- Date Published:
- Page Range / eLocation ID:
- 1 to 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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