Hybrid integrated mode-locked laser diodes with a silicon nitride extended cavity

Integrated semiconductor mode-locked lasers have shown promise in many applications and are readily fabricated using generic InP photonic integration platforms. However, the passive waveguides offered in such platforms have relatively high linear and nonlinear losses that limit the performance of these lasers. By extending such lasers with, for example, an external cavity the performance can be increased considerably. In this paper, we demonstrate for the first time that a high-performance mode-locked laser can be achieved with a butt-coupling integration technique using chip scale silicon nitride waveguides. A platform-independent SiN/SU8 coupler design is used to couple between the silicon nitride external cavity and the III/V active chip. Mode-locked lasers at 2.18 GHz and 15.5 GHz repetition rates are demonstrated with Lorentzian RF linewidths several orders of magnitude smaller than what has been demonstrated on monolithic InP platforms. The RF linewidth was 31 Hz for the 2.18 GHz laser.Comment: Submitted to Optics Expres

Ultra-dense III-V-on-silicon nitride frequency comb laser

A heterogeneously integrated III-V-on-silicon nitride mode-locked laser is demonstrated. The device is fabricated by microtransfer printing an InP/InAlGaAs-based multiple-quantum-well coupon. A dense comb with a 755 MHz repetition rate, a 1 Hz ASE limited RF linewidth and a 200 kHz optical linewidth is achieved

Hybrid integrated mode-locked laser using a GaAs-based 1064 nm gain chip and a SiN external cavity

External cavity mode-locked lasers could be used as comb sources for high volume application such as LIDAR and dual comb spectroscopy. Currently demonstrated chip scale integrated mode-locked lasers all operate in the C-band. In this paper, a hybrid-integrated external cavity mode-locked laser working at 1064 nm is demonstrated, a wavelength beneficial for optical coherence tomography or Raman spectroscopy applications. Additionally, optical injection locking is demonstrated, showing an improvement in the optical linewidth, and an increased stability of the comb spectrum

Micro-transfer printing of lithium niobate on silicon nitride

Successful micro-transfer printing of lithium niobate on a silicon nitride platform is demonstrated. A proof of concept electro-optical modulator is fabricated using this hybrid integration method which shows a half-wave voltage-length product VπLπ=5.5 Vcm and insertion losses of 7 dB

III-V-on-silicon mode-locked lasers with 1-GHz line spacing for dual-comb spectroscopy

We demonstrate dual-comb interferometry and spectroscopy with a III-V-on-silicon passively mode- locked laser of 1-GHz repetition rate and 1-THz span. We heterodyne the on-chip device with an electro-optic modulator comb for initial assessment. (C) 2020 The Author(s

A hybrid integration strategy for compact, broadband, and highly efficient millimeter-wave on-chip antennas

A novel hybrid integration strategy for compact, broadband, and highly efficient millimeter-wave (mmWave) on-chip antennas is demonstrated by realizing a hybrid on-chip antenna, operating in the [27.5-29.5] GHz band. A cavity-backed stacked patch antenna is implemented on a 600 mu m thick silicon substrate by using air-filled substrate-integrated-waveguide technology. A hybrid on-chip approach is adopted in which the antenna feed and an air-filled cavity are integrated on-chip, and the stacked patch configuration is implemented on a high-frequency printed circuit board (PCB) laminate that supports the chip. A prototype of the hybrid on-chip antenna is validated, demonstrating an impedance bandwidth of 3.7 GHz. In free-space conditions, a boresight gain of 7.3 dBi and a front-to-back ratio of 20.3 dB at 28.5GHz are achieved. Moreover, the antenna is fabricated using standard silicon fabrication techniques and features a total antenna efficiency above 90% in the targeted frequency band of operation. The high performance, in combination with the compact antenna footprint of 0.49 lambda(min) x 0.49 lambda(min), makes it an ideal building block to construct broadband antenna arrays with a broad steering range

III/V-on-lithium niobate amplifiers and lasers

We demonstrate electrically pumped, heterogeneously integrated lasers on thin-film lithium niobate, featuring electro-optic wavelength tunability. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Hybrid modeling approach for mode-locked laser diodes with cavity dispersion and nonlinearity

Semiconductor-based mode-locked lasers, integrated sources enabling the generation of coherent ultra-short optical pulses, are important for a wide range of applications, including datacom, optical ranging and spectroscopy. As their performance remains largely unpredictable due to the lack of commercial design tools and the poorly understood mode-locking dynamics, significant research has focused on their modeling. In recent years, traveling-wave models have been favored because they can efficiently incorporate the rich semiconductor physics of the laser. However, thus far such models struggle to include nonlinear and dispersive effects of an extended passive laser cavity, which can play an important role for the temporal and spectral pulse evolution and stability. To overcome these challenges, we developed a hybrid modeling strategy by unifying the traveling-wave modeling technique for the semiconductor laser sections with a split-step Fourier method for the extended passive laser cavity. This paper presents the hybrid modeling concept and exemplifies for the first time the significance of the third order nonlinearity and dispersion of the extended cavity for a 2.6 GHz III-V-on-Silicon mode-locked laser. This modeling approach allows to include a wide range of physical phenomena with low computational complexity, enabling the exploration of novel operating regimes such as chip-scale soliton mode-locking