Phys.org March 28, 2023 Optical parametric oscillators are widely used to generate coherent light at frequencies not accessible by conventional laser gain. However, chip-based parametric oscillators operating in the visible spectrum have suffered from pump-to-signal conversion efficiencies typically less than 0.1%. A team of researchers in the US (NIST, University of Maryland) demonstrated efficient optical parametric oscillators based on silicon nitride photonics that address frequencies between 260 and 510 THz. Pumping silicon nitride microrings near 385 THz yielded monochromatic signal and idler waves with unprecedented output powers in this wavelength range. They estimated on-chip output powers (separately for the signal […]
Tag Archives: Integrated photonics
Photonics – extending the spectrum
Nanowerk December 6, 2022 Despite remarkable manufacturing advantages, reliance on silicon-based waveguides currently limits the spectral window available to photonic integrated circuits (PICs). A team of researchers in the US (industry, UC Santa Barbara, Caltech) has developed a technique to enable photonic chips to operate in the visible-to-near-infrared spectrum by directly uniting III–V materials with silicon nitride waveguides on Si wafers. Using this technology, they fabricated a fully integrated PIC at photon energies greater than the bandgap of silicon, demonstrating essential photonic building blocks, including lasers, amplifiers, photodetectors, modulators, and passives, all operating at submicrometre wavelengths. Using this platform, they […]
Researchers develop laser that could ‘reshape the landscape of integrated photonics’
Phys.org October 24, 2022 A team of researchers in the US (University of Rochester, UC Santa Barbara, Caltech, Clemson University) has developed multi-color integrated laser that emits high-coherence light at telecommunication wavelengths allows laser-frequency tuning at record speeds and can be configured at the visible band. Using a hybrid integrated III-V/Lithium Niobate structure they demonstrated several essential capabilities that have not existed in previous integrated lasers. These include a record-high frequency modulation speed of 2 exahertz/s and fast switching at 50 MHz, both of which are made possible by integration of the electro-optic effect. The device co-lases at infrared and […]
Allying meta-structures with diverse optical waveguides for integrated photonics and more
Phys.org December 27, 2021 An international team of researchers (China, USA – Pennsylvania State University, Stanford University, Italy) reviewed recent advances in meta-structured waveguides that synergize various functional subwavelength photonic architectures with diverse waveguide platforms, such as dielectric or plasmonic waveguides and optical fibers, summarized foundational results and representative applications, cataloged brief physical models with explicit design tutorials, and highlighted how meta-optics can infuse new degrees of freedom to waveguide-based devices and systems. They discussed current challenges and outlined emerging opportunities of the field for applications in photonic integrated circuits, biomedical sensing, and artificial intelligence…read more. Open Access TECHNICAL ARTICLE
New device modulates visible light—without dimming it—with the smallest footprint and lowest power consumption
Phys.org November 22, 2021 Currently, the two most suitable materials are silicon nitride and lithium niobate. While both are highly transparent in the visible range, neither one provides very much tunability. A team of researchers in the US (Columbia University, Tufts University) developed a way to dramatically reduce both the size and the power consumption of a visible-spectrum phase modulator, from 1 mm to 10 microns and from tens of mW for π phase tuning to below 1 mW. The key to their solution was to use an optical resonator and to operate it in the strongly over-coupled regime. In […]
Novel physics gives rise to the highest coherence for microscopic lasers
Phys.org August 27, 2021 Despite considerable progress in microscale and nanoscale lasers the coherence length remains very limited. Researchers in Denmark explored the physics and applications of a new class of photonic devices using Fano interference which operates in bound-state-in the-continuum, induced by the Fano resonance. They showed experimentally as well as theoretically that the characteristics of such a bound-state-in-the-continuum can be harnessed to improve the coherence of the laser. They developed an advanced nanotechnology platform, called Buried Heterostructure Technology which allows realizing small, nanometer-sized regions of active material, where the light generation takes place, while the remaining laser structure […]