The microchip OPO device, based on the third-order (χ(3)) nonlinearity in a silicon nitride microresonator, produces output signal and idler fields widely separated from each other in frequency ( > 150 THz), and exhibits a pump-to-idler conversion efficiency up to 29 % with a corresponding output idler power of > 18 mW on-chip. This methodology can be readily applied to existing silicon photonics platforms with heterogeneously-integrated pump lasers, enabling flexible coherent light generation across a broad range of wavelengths with high output power and efficiency.

Perez et al. (2023), Nature communications

A self-injection locked laser with narrow linewidth down to 345 Hz is presented here, which is composed of distributed feedback (DFB) semiconductor laser and high quality (Q) factor silicon nitride (SiN) external cavity, with tunable sagnac loop reflector on the basis of add-drop type high Q microring resonator (MRR).

Su et al. (2022), SPIE digital library

We exploit the low-loss features of Si3N4 waveguides and demonstrate a hybrid laser comprising a GaSb gain chip with an integrated tunable Si3N4 Vernier mirror. At room temperature, the laser exhibited a maximum output power of 15 mW and a tuning range of 80 nm (1937 – 2017 nm).

Zia et al. (2022), Optics Letters

Guo et al. (2022), IEEE Xplore

Liu et al. (2022), IEEE Xplore

A hybrid InP/SiN tunable laser based on microring resonators exhibiting 40mW fibercoupled output power and 5kHz linewidth is demonstrated.

Calò et al. (2022)

We generate a quantum light source of eight pairs of correlated photons in a wavelength range of 25.6 nm within telecom wavelength using a SiN micro-ring with an FSR of 200 GHz.

Fan et al. (2022)

This paper demonstrates a widely tunable III-V/Si3N4 hybrid-integrated external cavity laser with maximum output power 34 mW, 2.5 kHz intrinsic linewidth, a relatively faster switching time ~ 60 μs, and side mode suppression ratio more than 70 dB over the tuning range of 58.5 nm. The external feedback circuit is based on 800-nm-thick Si3N4 waveguides with an optical confinement factor of 87%.

Guo et al., IEEE Xplore (2021)

We demonstrate an adaptable method for ultrastable control of low-energy femtosecond pulses based on common electro-optic modulation of a continuous-wave laser light source – the electro-optic modulation of a continuous-wave laser light source can also generate optical frequency combs.

Carlson et al., Science (2018)

In this work, we propose and experimentally demonstrate such an On-chip optical delay lines (ODLs) based on chirped waveguide Bragg gratings (CWBG). This device is fabricated on a low-loss 800-nm-height silicon nitride platform, combining 20.11-cm long index-chirped multi-mode spiral waveguide antisymmetric Bragg gratings with a directional coupler. The bandwidth of this circulator-free ODL is 23 nm. The total GD is 2864 ps and the delay-bandwidth product is 65.87 ns·nm, which both are the largest values achieved by on-chip CWBG reported to our knowledge.

Li et al. (2023), Optics Express

This study proposes and demonstrates a dispersive silicon–nitride OPA that allows for passive wavelength-tuned steering of a line beam with an elongated vertical beamwidth.

Bhandari et al. (2022), Scientific Reports

A 56 nm wavelength tuning range, 2.9 kHz linewidth, maximum output power 22.5 mW, and static frequency step bandwidth 56 GHz hybrid integrated external cavity laser is reported based on silicon nitride vernier microring resonators functioning as an optical bandpass filter. A frequency-modulated continuous-wave (FMCW) signal is generated under synchronous modulation with a chirp bandwidth of 7.68 GHz at a 1 kHz repetition rate.

Liu et al. (2022), IEEE Xplore

We fabricated in silicon nitride technology a proof of concept steerer with beam waist 0.36° ×0.175°, addressing a field of view of 15° ×2.8°. A new design iteration is also reported with and 0.24° ×0.16° beam waist and 15° ×11.2° field of view.

Munoz et al. (2022), IEEE Xplore

We propose and demonstrate an optical phased-array-based bidirectional grating antenna (BDGA) in silicon nitride waveguides. The manufactured BDGA could achieve an enhanced beam-steering efficiency of 0.148 deg/nm as well as a stable spectral emission response in the wavelength range of 1530–1600 nm.

Lee et al., Photonics Research (2022)

We present a hybrid integrated SiN-polymer OPA for realizing an efficient LiDAR. The polymeric modulators are integrated with a SiN power splitter and grating antenna.

Im et al., IEEE (2021)

Jha et al. (2021)

We propose and demonstrate a backward-emitting silicon nitride optical phased arrays (OPA) incorporating a reinforced grating vector, which provides efficient wavelength-tuned beam steering along the longitudinal direction.

Im et al., IEEE (2020)

We demonstrate that the all-optical inscription of second-order nonlinearity through the coherent photogalvanic effect allows not only degenerate but also non-degenerate sum-frequency generation in silicon nitride waveguides. Several multiphoton absorption processes can occur simultaneously, such that their quantum interference allows for the inscription of distinct charge gratings for quasi-phase matching of several second-order nonlinear processes within the same waveguide.

Yakar et al. (2023), SPIE digital library

For the first time, we report integrated firstorder quasi-phase-matched backward second-harmonic generation (BSHG) enabled by seeded all-optical poling. We carried out the demonstration in an integrated Si3N4 waveguide buried in SiO2 fabricated by LIGENTEC SA using its AN800 platform.

Yakar et al. (2023)

The microchip OPO device, based on the third-order (χ(3)) nonlinearity in a silicon nitride microresonator, produces output signal and idler fields widely separated from each other in frequency ( > 150 THz), and exhibits a pump-to-idler conversion efficiency up to 29 % with a corresponding output idler power of > 18 mW on-chip. This methodology can be readily applied to existing silicon photonics platforms with heterogeneously-integrated pump lasers, enabling flexible coherent light generation across a broad range of wavelengths with high output power and efficiency.

Perez et al. (2023), Nature Communications

The non-degenerate sum-frequency generation quasi-phase-matching gratings are reported on a silicon nitride chip, and supports the theory of coherent photogalvanic effect with time dynamics analysis

Yakar et al. (2022), Laser & Photonics Reviews

A quantum light source of eight pairs of correlated photons in a wavelength range of 25.6 nm within telecom wavelength using a SiN micro-ring with an FSR of 200 GHz.

Fan et al. (2022)

Based on the third-order (χ(3)) nonlinearity in a silicon nitride microresonator, an OPO device produces output signal and idler fields widely separated from each other in frequency (>150 THz), and exhibits a pump-to-idler conversion efficiency up to 29 % with a corresponding output idler power of >18 mW on-chip.

Perez et al. (2022)

CW-driven dissipative Kerr solitons in a high-Q standing-wave (intrinsic Q ~ 4 million) Fabry-Perot microresonator on a silicon nitride chip with an FSR ~ 19 GHz.

Wildi et al. (2022)

This paper thoroughly presents the design strategy to reliably attain an ultra-wide soliton microcomb with dual-modes separated by ∼10 GHz in the silicon nitride (Si3N4) platform.

Weng et al. (2022), APL Photonics

Huang et al. (2022)

Through sign-alternating the dispersion in a CMOS compatible silicon nitride waveguide, we present a scheme to get up to 1000 nm bandwidth Supercontinuum Generation, achieve an efficiency enhancement factor of 2800, and lower the pulse energy requirement from nanojoules to 6 picojoules.

Zia et al. (2022)

We implement thermally assisted electric-field poling, which allows charge carrier separation in the waveguide core and results in an effective second-order susceptibility (χ(2)) inside the Si3N4 waveguide, making linear electro-optic modulation accessible on the platform for the first time.

Zabelich et al. (2022)

We examine theoretically and experimentally the nonlinear coupling mechanism in a 1 THz repetition rate silicon nitride resonator and demonstrate four-wave mixing Bragg scattering between the different wavepackets forming the multi-color soliton, with the microcomb ranging over 150 THz, yielding a complex all-optical and integrated synthetic frequency lattice.

Moille et al. (2022)

We present optically reconfigurable quasi-phase-matching in large-radius silicon nitride microresonators, resulting in up to 12.5-mW on-chip second-harmonic generated power and a conversion efficiency of 47.6% W−1.

Nitiss et al., Nature Photonics (2022)

We demonstrate a photonic molecule composed of two coupled microring resonators on an integrated nanophotonic silicon nitride chip, designed to generate strongly squeezed light uncontaminated by noise from unwanted parasitic nonlinear processes.

Zhang et al., Nature Communications (2021)

We experimentally demonstrate the optical frequency division of an optically carried 3.6 THz reference down to 300 GHz through a dissipative Kerr soliton.

Tetsumoto et al., Nature Photonics (2021)

We report the generation of broadband single-mode (degenerate) quadrature squeezed vacuum from an integrated nanophotonic device based on two coupled silicon nitride microring resonators.

Zhang et al., scienceOPEN (2020)

We demonstrate a highly tunable second-harmonic generation in a silicon nitride integrated photonic platform.

Nitiss et al., Optics Letters (2020)

We report demonstrations of both quadrature squeezed vacuum and photon number difference squeezing generated via strongly driven spontaneous four-wave mixing below threshold in silicon nitride microring resonators.

Vaidya et al., arXiv (2019)

We experimentally demonstrate stimulated four-wave mixing in two linearly uncoupled integrated Si3N4 micro-resonators.

Tan et al., arXiv (2019)

We describe research on an optical-frequency synthesizer in a low-power chip-scale package that provides a laser output with a programmable optical frequency across 50 nm of bandwidth centered at 1550 nm, with a resolution smaller than one part in 10^14. Optical synthesizer is composed of a heterogeneously integrated III-V/Si tunable laser, which is guided by dual dissipative-Kerrsoliton frequency combs fabricated on separate silicon chips and pumped by off-chip laser.

Bowers et al., Gomatech (2019)

We use a heterogeneously integrated III–V/silicon tunable laser, which is guided by nonlinear frequency combs fabricated on separate silicon nitride chips and pumped by off-chip lasers. With this tunable-laser and frequency-comb system, we demonstrate synthesis across a 4-THz segment of the C-band with 1 Hz resolution. Any application of an optical-frequency source could benefit from the high-precision optical synthesis presented here.

Spencer et al., Nature (2018)

Here we show that quasi-phase-matching via periodic modulations of the waveguide structure on a silicon nitride photonic chip provides a useful mechanism to control the evolution of ultrafast pulses during supercontinuum generation.

Hickstein et al., Physical Review Letters (2017)

We demonstrate microresonators with programmable synthetic reflection which enables robust access to self-injection-locked microcombs operating exclusively in the single-soliton regime and with low threshold power.

Ulanov et al. (2023)

We demonstrate wireless communication in a 560-GHz band by using a photonic THz emitter based on photomixing of a 560-GHz-spacing soliton microcomb (using the SiN PIC of LIGENTEC) in a uni-travelling carrier photodiode together with a THz receiver of Schottky barrier diode. The on-off keying data transfer with 2-Gbit/s achieves a Q-factor of 3.4, thus, satisfying the limit of forward error correction.

Tokizane et al. (2023)

We experimentally demonstrate that multiple microcombs can coexist in monochromatically pumped Si3N4 microresonators.

Wu et al., Optics Letters (2022)

A soliton microcomb prototype with a microring of 75 GHz FSR on silicon nitride chip coupled to fiber array.

Xi et al. (2022)

In this paper, we investigate the switchability of dissipative cnoidal waves (DCWs) based on dual-coupled Si3N4 microresonators.

Wu et al., Optics Express (2021)

A dissipative Kerr-microresonator soliton comb is scanned by 70 GHz in 500µs, 50 GHz in 125µs, and 25 GHz in 50µs (= 500 THz/s). Furthermore, we propose and demonstrate a method to measure the frequency shift of all comb modes, in which an imbalanced Mach–Zehnder interferometer with two outputs with different wavelengths is used.

Kuse et al., Optics Letters (2021)

We propose an integrated photonics interposer to replace discrete components of microcomb based systems (microcombs, other nonlinear elements, lasers and photodetectors, etc) around 1550 nm by collecting, routing and interfacing octave-wide microcomb-based optical signals between photonic chiplets and heterogeneously integrated devices using silicon nitride photonics.

Rao et al., Light Science & Applications (2021)

By employing Pound–Drever–Hall locking and a microheater on the silicon nitride microresonator, we show continuous scanning of the soliton comb modes across nearly the full free-spectral range of the microresonator without losing soliton operation, while spectral features with a bandwidth as small as 5 MHz are resolved.

Kuse et al., Optics Letters (2020)

We report a comprehensive study of low-power, octave-bandwidth, single-soliton microresonator frequency combs in both the 1550 nm and 1064 nm bands, and get direct soliton generation with less than 40 mW of chip-coupled laser power utilizing fully integrated silicon nitride Kerr microresonators.

Briles et al., arXiv (2020)

A microphotonic astrocomb is demonstrated via temporal dissipative Kerr solitons in photonic-chip-based silicon nitride microresonators, directly providing a spurious-free spectrum of resolvable calibration lines.

Obrzud et al., Nature Photonics (2019)

A broadband visible (VIS) blue-to-red, 10 GHz repetition rate frequency comb is generated by combined spectral broadening and triple-sum-frequency generation in an on-chip silicon nitride waveguide.

Obrzud et al., Optics Letters (2019)

Manurkar et al., OSA Continuum (2018)

We demonstrate robust frequency-control strategies for near-infrared, octave-bandwidth soliton frequency combs created with nanofabricated silicon nitride ring resonators. The comb links wavelengths between 767 and 1556 nm from a 1064 nm pump laser, and the mode frequencies of the comb are spaced by 1 THz.

Yu et al., Physical Review Applied (2018)

We explore the creation of an octave-spanning, 15-GHz repetition-rate microcomb suitable for both f−2f self-referencing and optical-frequency comparisons across the near infrared. Efficient silicon-nitride waveguides provide a supercontinuum spanning 700 to 2100 nm, enabling both offset-frequency stabilization and optical-frequency measurements with >100 nW per mode.

Lamb et al., Physical Review Applied (2017)

Using a continuous wave–pumped, dispersion-engineered, integrated silicon nitride microresonator, we generated continuously circulating temporal dissipative Kerr solitons.

Brasch et al., Science (2016)

Here, we demonstrate the storage and recall of the entangled state of two telecom photons generated from an integrated photonic chip based on silicon nitride. Combining the natural narrow linewidth of the entangled photons and long storage time of 167Er3+ ions, we achieve storage time of 400 ns, more than one order of magnitude longer than in previous works.

Jiang et al., (2022)

We demonstrate controlled-NOT (CNOT) operation of a silicon nitride photonic integrated circuit using path-entangled photon pairs from a silicon-photonic integrated circuit as logical inputs, and the CNOT gate is by combining several silicon-nitride Mach–Zehnder interferometers for a linear-optical quantum gate. The fully packaged photonic circuits with electrical wire bonding and optical fiber bonding measures the logical-basis fidelity of CNOT operation better than 81%.

Lee et al., Optics Communications (2022)

A quantum light source of eight pairs of correlated photons in a wavelength range of 25.6 nm within telecom wavelength using a SiN micro-ring with an FSR of 200 GHz.

Fan et al. (2022)

Here we introduce a full-stack hardware−software system for executing many-photon quantum circuit operations using integrated nanophotonics on a silicon nitride chip: a programmable chip, operating at room temperature and interfaced with a fully automated control system.

Arrazola et al., Nature (2021)

We report demonstrations of both quadrature squeezed vacuum and photon number difference squeezing generated via strongly driven spontaneous four-wave mixing below threshold in silicon nitride microring resonators.

Vaidya et al., arXiv (2019)

We present the design and experimental characterization of a silicon nitride pulse interleaver based on coupled resonator optical waveguide filters.

Zazzi et al. (2023), Optics Express

Highlights the capability of commercial SiN foundries to fabricate ultra-small (7.4 mm × 2 mm), high-resolution, high-throughput AWG spectrographs on a chip suitable for both ground- and space-based telescopes.

Gatkine et al. (2022)

A 8.75 × 3 mm silicon nitride chip with a square waveguide cross-section of 800 × 800 nm is used to fabricate a continuous-output, curved focal-plane photonic Arrayed Waveguide Grating (AWG) with a resolving power of 12,000, a free-spectral range of 18 nm, and a wide operational band of 1425-1650 nm, which allows a continuous sampling of the spectrum in high precision spectroscopy.

Gatkine et al. (2022), SPIE digital library

We discuss the design and demonstration of 4-channel coarse wavelength-division (de-)multiplexers based on cascaded Mach-Zehnder interferometer (MZI) lattice filters and arrayed waveguide gratings (AWG) on a 150 nm silicon nitride ( Si3N4 ) platform.

Stanley Cheung and Michael R.T Tan, Journal of Lightwave Technology (2020)

Low-loss, fabrication-tolerant Si3N4 CWDM lattice filters and AWGs are demonstrated for 990 – 1065nm bottom-emitting VCSELs. Channel separation of 25 nm, XT <; -35 dB and -20 dB are reported with temperature shift of 14.5 pm/°C.

Stanley Cheung and Michael R.T Tan, IEEE (2020)

We present a hybrid integrated SiN-polymer OPA for realizing an efficient LiDAR. The polymeric modulators are integrated with a SiN power splitter and grating antenna.

Im et al., IEEE (2021)

Microwave-frequency acousto-optic modulation is realized by exciting high-overtone bulk acoustic wave resonances (HBAR) in the photonic stack on a silicon nitride photonic integrated chip. A Si3N4-based optical isolator is demonstrated by spatiotemporal modulation, with over 17 dB isolation achieved.

Tian et al., Nature Communications (2020)

Here we demonstrate InGaAs/InP modified uni-traveling carrier photodiodes on Si3N4 waveguides with 20 nA dark current, 20 GHz bandwidth, and record-high external (internal) responsivities of 0.8 A/W (0.94 A/W) and 0.33 A/W (0.83 A/W) at 1550 nm and 1064 nm, respectively.

Yu et al., Optics Express (2020)

This work demonstrates a heterogeneous platform by bonding lithium niobate (LN) thin films onto a silicon nitride (Si3N4) waveguide layer on silicon.

Chang et al., Optics Letters (2017)

Highlights the capability of commercial SiN foundries to fabricate ultra-small (7.4 mm × 2 mm), high-resolution, high-throughput AWG spectrographs on a chip suitable for both ground- and space-based telescopes.

Gatkine et al. (2022)

A 8.75 × 3 mm silicon nitride chip with a square waveguide cross-section of 800 × 800 nm is used to fabricate a continuous-output, curved focal-plane photonic Arrayed Waveguide Grating (AWG) with a resolving power of 12,000, a free-spectral range of 18 nm, and a wide operational band of 1425-1650 nm, which allows a continuous sampling of the spectrum in high precision spectroscopy.

Gatkine et al. (2022), SPIE digital library

By employing Pound–Drever–Hall locking and a microheater on the silicon nitride microresonator, we show continuous scanning of the soliton comb modes across nearly the full free-spectral range of the microresonator without losing soliton operation, while spectral features with a bandwidth as small as 5 MHz are resolved.

Kuse et al., Optics Letters (2020)

We describe infrared RV spectroscopy at the 10 m Hobby–Eberly Telescope that leverages a 30 GHz electro-optic laser frequency comb with a nanophotonic supercontinuum to calibrate the Habitable Zone Planet Finder spectrograph. The frequency comb generation includes a silicon nitride chip (5  mm×3  mm) on which nanophotonic waveguides are patterned.

Metcalf et al., Optica (2019)

We demonstrate robust frequency-control strategies for near-infrared, octave-bandwidth soliton frequency combs created with nanofabricated silicon nitride ring resonators. The comb links wavelengths between 767 and 1556 nm from a 1064 nm pump laser, and the mode frequencies of the comb are spaced by 1 THz.

Yu et al., Physical Review Applied (2018)

In this work, we present for the first time a 4×4 Generalized Mach Zehnder Interferometer (GMZI) incorporated on a Si3N4 photonic integration platform and we experimentally demonstrate its operation as a variable power splitter.

Kovaios et al. (2023), SPIE digital library

In this work, we demonstrate a monolithic, fully complementary metal-oxide-semiconductor compatible, nonlinear Mach-Zehnder interferometer isolator based on third order optical nonlinearity, which is broadband, low insertion loss and easy to fabricate. In this proof of principle study, we show up to 15 dB isolation with 0.4 dB insertion loss and a device footprint of 0.4 mm2 which can easily be improved on further. Not only can such a device be used for integrated optical systems but also for the fibre based optical systems.

Singh et al. (2023), Optics Express

In this study, we demonstrate a hybrid OPA that capitalizes on a silicon nitride line beam emitter based on tapered waveguides array, which facilitates efficient line beam scanning exhibiting flexible vertical field-of-views (FOVs) at a wavelength of 1550 nm.

Wang et al. (2022), IEEE Xplore

This study proposes and demonstrates a dispersive silicon–nitride OPA that allows for passive wavelength-tuned steering of a line beam with an elongated vertical beamwidth.

Bhandari et al. (2022), Scientific Reports

We fabricated in silicon nitride technology a proof of concept steerer with beam waist 0.36° ×0.175°, addressing a field of view of 15° ×2.8°. A new design iteration is also reported with and 0.24° ×0.16° beam waist and 15° ×11.2° field of view.

Munoz et al. (2022), IEEE Xplore

We propose and demonstrate an optical phased-array-based bidirectional grating antenna (BDGA) in silicon nitride waveguides. The manufactured BDGA could achieve an enhanced beam-steering efficiency of 0.148 deg/nm as well as a stable spectral emission response in the wavelength range of 1530–1600 nm.

Lee et al., Photonics Research (2022)

We present the design of Vernier ring-inspired reflectors based on an 800nm- thick Si3N4 platform providing a TE fundamental mode with an effective index close to 1.71 for a width of 800nm, a group index close to 2.08 at λ=1550nm wavelength, and propagation losses as low as 0.2dB/cm. The proposed thick- Si3N4 designs are based on a simple dual ring Vernier configuration achieving an experimental FSR near 38nm and a 15dB side-mode suppression.

Chatzitheocharis et al., SPIE digital library (2021)

We present a hybrid integrated SiN-polymer OPA for realizing an efficient LiDAR. The polymeric modulators are integrated with a SiN power splitter and grating antenna.

Im et al., IEEE (2021)

We propose and demonstrate a backward-emitting silicon nitride optical phased arrays (OPA) incorporating a reinforced grating vector, which provides efficient wavelength-tuned beam steering along the longitudinal direction.

Im et al., IEEE (2020)

We propose a silicon nitride polarization beam splitter that exploits serially cascaded asymmetric directional couplers (ADCs), leading to a high polarization extinction ratio (PER) over a broad bandwidth. The measured transverse-electric and transverse-magnetic PERs were determined to be above 23 dB and 10 dB over an 80-nm bandwidth, respectively, spanning 𝜆=1520−1600nm.

Bhandari et al., Optics Letters (2020)

Here we investigate effects of proton radiation on high-Q (𝒪(10^6)) silicon nitride microresonators formed by a waveguide ring. We show that the irradiation with high-energy protons has no lasting effect on the linear optical losses of the microresonators.

Brasch et al., Optics Express (2014)

We present a high performance silicon nitride photonic integrated circuit platform operating at visible wavelengths, accessible through the commercial foundry, LIGENTEC. Propagation losses were measured across the visible spectrum from 450 nm to 850 nm.

Smith et al., Optical Materials Express (2023)

Silicon nitride (SiN) photonic integrated circuits (PICs) are promising in visible light applications such as OCT, Cytometry, sensors and light sources. LIGENTEC is introduced as one of the foundries offering open-access generic SiN PICs.

Porcel et al., Science Direct (2018)