Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong demand. Due to two-photon absorption in silicon, however, much nonlinear research is shifting towards unconventional photonics platforms. In this work, we demonstrate the generation of an octave-spanning coherent supercontinuum in a silicon waveguide covering the spectral region from the near- to shortwave-infrared. With input pulses of 18 pJ in energy, the generated signal spans the wavelength range from the edge of the silicon transmission window, approximately 1.06 to beyond 2.4 μm, with a −20 dB bandwidth covering 1.124–2.4 μm. An octave-spanning supercontinuum was also observed at the energy levels as low as 4 pJ (−35 dB bandwidth). We also measured the coherence over an octave, obtaining , in good agreement with the simulations. In addition, we demonstrate optimization of the third-order dispersion of the waveguide to strengthen the dispersive wave and discuss the advantage of having a soliton at the long wavelength edge of an octave-spanning signal for nonlinear applications. This research paves the way for applications, such as chip-scale precision spectroscopy, optical coherence tomography, optical frequency metrology, frequency synthesis and wide-band wavelength division multiplexing in the telecom window.
Long-term stable, sub-femtosecond timing distribution over a 1.2-km polarization-maintaining (PM) fiber-optic link using balanced optical cross-correlators for link stabilization is demonstrated. Novel dispersion-compensating PM fiber was developed to construct a dispersion-slope-compensated PM link, which eliminated slow timing drifts and jumps previously induced by polarization mode dispersion in standard single-mode fiber. Numerical simulations of nonlinear pulse propagation in the fiber link confirmed potential sub-100-as timing stability for pulse energies below 70 pJ. Link operation for 16 days showed ~0.6 fs RMS timing drift and during a 3-day interval only ~0.13 fs drift, which corresponds to a stability level of 10(-21).
Mid-infrared laser sources are of great interest for various applications, including light detection and ranging, spectroscopy, communication, trace-gas detection, and medical sensing. Silicon photonics is a promising platform that enables these applications to be integrated on a single chip with low cost and compact size. Silicon-based high-power lasers have been demonstrated at 1.55 μm wavelength, while in the 2 μm region, to the best of our knowledge, high-power, high-efficiency, and monolithic light sources have been minimally investigated. In this Letter, we report on high-power CMOS-compatible thulium-doped distributed feedback and distributed Bragg reflector lasers with single-mode output powers up to 267 and 387 mW, and slope efficiencies of 14% and 23%, respectively. More than 70 dB side-mode suppression ratio is achieved for both lasers. This work extends the applicability of silicon photonic microsystems in the 2 μm region.
Laser sources in the mid-infrared are of great interest due to their wide applications in detection, sensing, communication and medicine. Silicon photonics is a promising technology which enables these laser devices to be fabricated in a standard CMOS foundry, with the advantages of reliability, compactness, low cost and large-scale production. In this paper, we demonstrate a holmium-doped distributed feedback laser monolithically integrated on a silicon photonics platform. The AlO:Ho glass is used as gain medium, which provides broadband emission around 2 µm. By varying the distributed feedback grating period and AlO:Ho gain layer thickness, we show single mode laser emission at wavelengths ranging from 2.02 to 2.10 µm. Using a 1950 nm pump, we measure a maximum output power of 15 mW, a slope efficiency of 2.3% and a side-mode suppression ratio in excess of 50 dB. The introduction of a scalable monolithic light source emitting at > 2 µm is a significant step for silicon photonic microsystems operating in this highly promising wavelength region.
We present a CMOS-compatible, Q-switched mode-locked integrated laser operating at 1.9 µm with a compact footprint of 23.6 × 0.6 × 0.78mm. The Q-switching rate is 720 kHz, the mode-locking rate is 1.2 GHz, and the optical bandwidth is 17nm, which is sufficient to support pulses as short as 215 fs. The laser is fabricated using a silicon nitride on silicon dioxide 300-mm wafer platform, with thulium-doped Al 2 O 3 glass as a gain material deposited over the silicon photonics chip. An integrated Kerr-nonlinearity-based artificial saturable absorber is implemented in silicon nitride. A broadband (over 100 nm) dispersioncompensating grating in silicon nitride provides sufficient anomalous dispersion to compensate for the normal dispersion of the other laser components, enabling femtosecondlevel pulses. The laser has no off-chip components with the exception of the optical pump, allowing for easy co-integration of numerous other photonic devices such as supercontinuum generation and frequency doublers which together potentially enable fully on-chip frequency comb generation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.