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International audience; The tremendous demand for low-cost, low-consumption and high-capacity optical transmitters in data centers challenges the current InP-photonics platform. The use of silicon (Si) photonics platform to fabricate photonic integrated circuits (PICs) is a promising approach for low-cost large-scale fabrication considering the CMOS-technology maturity and scalability. However, Si itself cannot provide an efficient emitting light source due to its indirect bandgap. Therefore, the integration of III-V semiconductors on Si wafers allows us to benefit from the III-V emitting properties combined with benefits offered by the Si photonics platform. Direct epitaxy of InP-based materials on 300 mm Si wafers is the most promising approach to reduce the costs. However, the differences between InP and Si in terms of lattice mismatch, thermal coefficients and polarity inducing defects are challenging issues to overcome. III-V/Si hetero-integration platform by wafer-bonding is the most mature integration scheme. However, no additional epitaxial regrowth steps are implemented after the bonding step. Considering the much larger epitaxial toolkit available in the conventional monolithic InP platform, where several epitaxial steps are often implemented, this represents a significant limitation. In this paper, we review an advanced integration scheme of AlGaInAs-based laser sources on Si wafers by bonding a thin InP seed on which further regrowth steps are implemented. A 3 µm-thick AlGaInAs-based MutiQuantum Wells (MQW) laser structure was grown onto on InP-SiO2/Si (InPoSi) wafer and compared to the same structure grown on InP wafer as a reference. The 400 ppm thermal strain on the structure grown on InPoSi, induced by the difference of coefficient of thermal expansion between InP and Si, was assessed at growth temperature. We also showed that this structure demonstrates laser performance similar to the ones obtained for the same structure grown on InP. Therefore, no material degradation was observed in spite of the thermal strain. Then, we developed the Selective Area Growth (SAG) technique to grow multi-wavelength laser sources from a single growth step on InPoSi. A 155 nm-wide spectral range from 1515 nm to 1670 nm was achieved. Furthermore, an AlGaInAs MQW-based laser source was successfully grown on InP-SOI wafers and efficiently coupled to Si-photonic DBR cavities. Altogether, the regrowth on InP-SOI wafers holds great promises to combine the best from the III-V monolithic platform combined with the possibilities offered by the Si photonics circuitry via efficient light-coupling.

In this work, we present an advanced heterogeneous integration scheme which consists in integrating a thin InP layer by wafer-bonding onto a silicon wafer (InPoSi) on which a regrowth step of III-V materials is implemented. Vertical p-i-n AlGaInAs lasers obtained from a single Selective Area Growth (SAG) step on InPoSi were fabricated. Thanks to SAG, the AlGaInAs-MQW structures successfully cover a PL range of 160 nm in the C+L band. Based on these structures, a 5- channel laser array was fabricated. The latter successfully covers a 155 nm-wide spectral band from 1515 nm to 1670 nm with a maximum output power of 20 mW under continuous-wave regime at 20°C. High thermal stability up to 70°C is demonstrated with a characteristic temperature of 69°C for the lasers emitting from 1515 nm to 1600 nm.

International audience; We present a complete characterization of reflective electroabsorption modulators (EAMs) monolithically integrated with semiconductor optical amplifiers (SOAs), components that are capable of operating beyond 50 Gb/s in the C-band. The devices are based on GaInAsP multiple quantum wells on InP substrate, leveraging semi-insulating buried heterostructure waveguide definition and butt-joint integration technologies. Different device configurations, based on 80-μm and 150-μm long EAMs, are fabricated and characterized in both static and dynamic modes. The frequency response of the 80-μm long EAM is still flat at 26.5 GHz (setup upper limit) whereas the 150-μm long EAM exhibits a 3-dB cutoff bandwidth of 23 GHz. A zero-chirp is achieved for EAM reverse bias voltages between −1.2 V and −1.5 V depending on the wavelength. Under large-signal modulation, the frequency chirp induced by the shorter EAM is almost half that of the longer EAM, with their respective peak values being +1.5/−2 GHz and +3.2/−3.7 GHz (rising/falling edges) at 1545 nm (−1.3 V bias, 2.6 V voltage swing). We obtained high dynamic extinction ratios of ~14.5 dB and ~8 dB from the longer and the shorter EAMs, respectively, when they are operated at 25 Gb/s using non-return-to-zero coding. Finally, we achieved 12 km and 16 km colorless transmissions in the C-band (between 1530 nm and 1545 nm) over a standard single-mode fiber without equalization using the 150-μm and the 80-μm EAMs, respectively, with 4.5 dB and 2.5 dB dispersion penalties at a bit error rate of 10E−3.

International audience; We experimentally present a 10-Gb/s Fiber Wireless IFoF/V-band uplink of four625Mbaud 16QAM signals with a linear, high-power monolithically integrated reflective electroabsorptionmodulator with semiconductor optical amplifier for 5G mmWave fronthaul networks.

Vertical p-i-n lasers integrated by wafer-bonding and regrowth on a heterogeneous InP-on-SOI wafer are presented. We demonstrate for the first time lasers based on regrown III-V active regions efficiently coupled to Si-photonic DBR cavities.

Vertical p-i-n AlGaInAs lasers obtained from a single Selective Area Growth (SAG) step on a thin InP layer bonded to silicon wafers are presented. A PL extension from 1490 nm to 1645 nm was demonstrated on InP-SOI wafer. Based on this result, a record of 155 nm wide spectral range was obtained for FP lasers on InP-SiO 2 /Si wafer.

We present a colorless transmitter based on a reflective electroabsorption modulator (EAM) monolithically integrated with a semiconductor optical amplifier (SOA). A semi-insulating buried heterostructure (SI-BH) technology is used to define the device waveguide structures. The integration of the SOA allows to fully compensate for insertion losses. We observe up to +2 dB net gain in the fiber-coupled output power, for 90 mA SOA bias current. We demonstrate 25 Gb/s operation with non-return-to-zero (NRZ) modulation format, with a dynamic extinction ratio (DER) up to 14 dB for 2.6 V peak-to-peak EAM driving voltage. Colorless operation is demonstrated over 15 nm spectral range in the C-band. We achieved 10 km dispersion limited transmission distance at 25 Gb/s NRZ with a penalty of 3 dB at 10−3 bit error rate (BER).

In this work, we present the fabrication process of a $3~\mu \text{m}$ -thick AlGaInAs-based vertical p-i-n laser diode structure grown on a directly bonded InP-SiO2/Si (InPoSi) substrate. High-quality epitaxial growth on InPoSi is reported. Based on these structures, the fabrication process of Fabry-Perot broad lasers is presented. Device performance is compared to the ones obtained from the same growth run on an InP substrate as a reference. High electrical properties of the n and p contacts are demonstrated. Lasing operation in the pulse regime is shown up to 50°C. Threshold current densities as low as 0.4 kA/cm 2 at 20°C are obtained for the laser on InPoSi, comparable to the ones obtained for the reference on InP substrate.

We study the impact of transmitter chirp parameter (effective α-factor) on the chromatic-dispersion-induced power penalty in 50-Gbit/s TDM-PON. We experimentally show interplay of chirp and dispersion using 50G-class integrated EML-SOA driven in distinct operating points.

Fabry-Perot laser arrays based on vertical p-i-n laser diode structures grown on InP layer directly bonded to Si wafer is presented. Lasing emission covering the C+L bands is achieved by means of a single-epitaxy Selective Area Growth (SAG) technology.

We demonstrate burst-mode upstream and continuous-mode downstream transmission in a 50G TDM-PON system, achieving up to 33-dB loss budget with a maximum of 77-km SMF transmission before any equalization. The system is enabled by semiconductor optical amplifiers at the transceivers.

We present a 56Gbaud/s $13\mu{m}$ electro-absorption modulated laser, based on semi-insulated buried waveguide technology. A dynamic extinction ratio of 8.4dB, with 1. 8dBm fiber coupled average power, and 112Gb/s PAM4 transmission, with a $BER=10^{-3}$ , are demonstrated.

We present a study of the performance enhancement of a quantum dot infrared photodetector (QDIP), by means of complementary split-ring resonator (CSRR) nano-antennae. The QDIP is based on an asymmetric heterostructure containing a single layer of self-assembled InAs/GaAs quantum dots (QDs). The proximity of the QD plane to the top contact layer is exploited for the coupling with the near-field of the CSRR modes. The co-existence of the CSRR LC mode, at λLC = 7.4 μm, and of non-localized Bragg-like modes, is observed for the two-dimensional array of nano-antennae implemented on the QDIP. At λLC and a temperature T = 10 K, the antenna coupled device is characterized by a responsivity of 44 μA/W and a specific detectivity D* = 1.5 × 108Jones. For the highly localized LC mode, enhancements of a factor 1.7 in responsivity and 2.1 in specific detectivity are observed. Within the sub-wavelength LC mode effective surface, normalizing the overall response to the active surface of the detector, a responsivity enhan...

We present a study of the dynamic properties of electrons tunneling from an InGaAs quantum well to self assembled InAs quantum dots. The experiments were conducted on three highly asymmetric quantum dot infrared photodetectors, where the quantum well and quantum dots were separated by a composite GaAs/AlGaAs/GaAs barrier, which varied from 3.5 nm to 7.0 nm. We performed interband (photoluminescence) and intraband (photocurrent) measurements to characterize the spectral properties of the well and the dots. The photoluminescence measurements revealed that the two nanostructures are decoupled when the device is at zero bias. By intraband pump-probe experiments and photocurrent saturation experiments, we were able to extrapolate a refilling time τ from the well to the dots, which varied from a few μs for the thinnest barrier and hundreds of μs for the thickest one. The extracted values are in good agreement with characteristic tunneling times computed by using a model based on the theoretically predicted tran...