Efficient telecom-to-visible spectral translation through ultralow power nonlinear nanophotonics

Abstract

The ability to spectrally translate lightwave signals in a compact, low-power platform is at the heart of the promise of nonlinear nanophotonic technologies. For example, a device to link the telecommunications band with visible and short near-infrared wavelengths can enable a connection between high-performance chipintegrated lasers based on scalable nanofabrication technology with atomic systems used for time and frequency metrology. While second-order nonlinear (χ (2) ) systems are the natural approach for bridging such large spectral gaps, here we show that third-order nonlinear (χ (3) ) systems, despite their typically much weaker nonlinear response, can realize spectral translation with unprecedented performance. By combining resonant enhancement with nanophotonic mode engineering in a silicon nitride microring resonator, we demonstrate efficient spectral translation of a continuous-wave signal from the telecom band (≈ 1550 nm) to the visible band (≈ 650 nm) through cavity-enhanced four-wave mixing. We achieve such translation over a wide spectral range >250 THz with a translation efficiency of (30.1 ± 2.8) % and using an ultra-low pump power of (329 ± 13) µW. The translation efficiency projects to (274 ± 28) % at 1 mW and is more than an order of magnitude larger than what has been achieved in current nanophotonic devices.

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

“…As a result, such ultra-high-Q resonators can suffer from significant waveguide geometry variation, which is problematic in many applications that rely upon accurate control of dimensions. For example, the detection of carrier envelope offset frequency of microcombs for self-referencing or the efficient spectral translation between visible and infrared light require precise dimensional control of the waveguide cross section[37]. Compared to dielectrics, the epitaxial growth for semiconductors enables atomic scale accuracy of material thickness with high uniformity, providing a good solution to dimension control in nonlinear photonics.One commonly used step in the fabrication of high Q resonators, but not critical in AlGaAsOI process, is a high temperature (>1000 ᵒ C) anneal, which reduces the O-H and N-H bonds in deposited Si3N4 and SiO2 layers, as such bonds cause absorption losses.However, this step is not compatible with the fabrication of standard photonic pg 15.…”

Nanostructured amorphous gallium phosphide on silica for nonlinear and ultrafast nanophotonics

“…over the entire volume. 3 This property has already been employed to successfully explore second [4][5][6][7][8] and third [9][10][11] harmonic generation as well as frequency mixing 12,13 with dielectric nanoparticles, exceeding the achieved efficiencies of comparable plasmonic systems. Furthermore, the lack of linear absorption reduces photon-electron interactions and thus promotes all-dielectric structures as a platform for non-destructive all-optical switching, sensing and data processing, [14][15][16][17][18][19] in particular at high powers above the damage threshold of plasmonic metals.…”

Ultra-efficient frequency comb generation in AlGaAs-on-insulator microresonators

“…As a result, such ultra-high-Q resonators can suffer from significant waveguide geometry variation, which is problematic in many applications that rely upon accurate control of dimensions. For example, the detection of carrier envelope offset frequency of microcombs for self-referencing or the efficient spectral translation between visible and infrared light require precise 50 2.05 6.2 × 10 −19 ∼1.5 3.2 × 10 6 10 (500 GHz) Hydex 51 1.7 1.15 × 10 −19 ∼2 1 × 1 0 6 50 (200 GHz) Si 52 3.47 5 × 10 −18 ∼2 5.9 × 10 5 3.1 (127 GHz) GaP 53 3 dimensional control of the waveguide cross section 41 . Compared with dielectrics, the epitaxial growth for semiconductors enables atomic scale smooth surfaces (see Supplementary Fig.…”

“…Since AlGaAsOI supports both of the most efficient second-and thirdorder nonlinear effects in integrated photonics, it holds the potential to simultaneously incorporate self-referencing using SHG together with octave-spanning Kerr comb generation. It should also be noted that in quantum optics, efficient χ (2) and χ (3) processes are important for several processes, e.g., the spontaneous parametric down-conversion 46 and spontaneous four wave mixing 41 . Moreover, other nonlinear properties of AlGaAs, such as the photoelastic and piezoelectric effects 47 , can be harnessed by utilizing the high-Q cavity in optomechanics.…”