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Increasing demand for higher data rates in data centers and high-performance computing systems require optical interconnects that support more than 100 Gbps-per-lane. Meanwhile, as optics are packed ever closer to Ethernet switches and electronic processors, both operating temperatures and power consumptions increase, resulting in increasing operational and environmental costs. In this work we present our recent results on a two-channel energy-efficient directly-modulated membrane laser array on SiO2/Si with ∼60-GHz 3-dB bandwidth, that can support both 100 Gbps-per-lane modulations as well as very small form-factors and power consumptions. The extension to 60 GHz bandwidths denotes a ∼26.3% increase compared to previous works, and it was achieved based on an optimized distributed-reflector laser design for maximizing the photon-photon resonance effect. Based on the fabricated two-channel DML array, 200 Gbps (2×112-Gbps NRZ) with laser operating energy-per-bit cost of less than 0.3 pJ/bit over 2-km transmissions, and the feasibility of 400 Gbps (2×200-Gbps PAM-4) transmissions are demonstrated. Finally, the temperature dependence of the PPR effect and its impact on the E-O response have been studied both experimentally and with numerical simulations for temperatures up to 75 °C for the first time. [ABSTRACT FROM AUTHOR]

We fabricate a membrane InP-based electro-absorption modulator (EAM), in which an InGaAsP-based multiple-quantum-well (MQW) absorption region is buried with an InP layer, on Si-waveguide circuits. By optical coupling between the MQW absorption region and Si core, a low-loss and large-absorption-length (300-μm-long) supermode waveguide is designed to suppress electric-field screening at high optical input power. The EAM is fabricated by combining direct bonding of the MQW layer and regrowth of the InP layer on a thin InP template bonded on a silicon-on-insulator wafer. The fabricated membrane EAM shows an on-chip loss of less than 4 dB at wavelengths over 1590 nm and temperatures from 25 to 50 °C. Since the membrane lateral p-i-n diode structure is beneficial for reducing the RC time constant of a lumped-electrode InP-based EAM, the EO bandwidth of the EAM is around 50 GHz without a 50-ohm termination up to fiber-input power of 10 dBm. Using the device, we demonstrate clear eye openings for 56-Gbit/s NRZ and 112-Gbit/s PAM4 signals at temperatures from 25 to 50 °C. [ABSTRACT FROM AUTHOR]

We investigate strong excitonic absorption and large nonlinear wavelength shifts in buried multiple-quantum-well photonic crystal L3 nanocavities that well confine the carriers. The confined carriers can survive as long as the radiative lifetime because carrier diffusion is negligible and surface recombination is well suppressed. In addition, strong optical confinement and small mode volume provided by photonic crystals can enhance excitonic nonlinearity. Therefore, our structure shows a strong excitonic effect that induces large refractive index changes by exciton bleaching and exhibits a large cavity-frequency shift. Our results will contribute to the development of ultralow energy all-optical switching devices in the future. [ABSTRACT FROM AUTHOR]

This article presents a 2-channel 4-level pulse amplitude modulation (PAM4) transmitter front-end consisting of a 2-channel PAM4 shunt laser diode (LD) driver and flip-chip-bonded 1.3-μm LD array-on-Si that has the highest power efficiency yet reported for PAM4 transmitter front-ends. The driver was designed and fabricated using 65-nm CMOS technology, and the LD array-on-Si was fabricated using 1.3-μm membrane LD array-on-Si technology. To decrease the power consumption, the front-end does not use a high-speed digital-to-analog converter (DAC) or linear driver for generating the PAM4 signals. Instead, to generate clear PAM4 signals, the shunt LD driver incorporates DAC, and equalizing functions. The driver was designed with a photonic-electronic conversion system in SPICE, and the transmitter front-end was implemented with flip-chip-bonding interconnection between the driver and LD array-on-Si. The resulting 2-channel PAM4 transmitter front-end has high power efficiency. Our experiments show that in simultaneous operation, each channel could transmit 53-Gbps PAM4 signals, resulting in a power efficiency of 0.57 mW/Gbps. They also show that feed-forward equalization (FFE) with only 10 taps is enough for 2-km-long standard single-mode fiber (SSMF) transmission of 53-Gbps PAM4 signals with a bit error rate (BER) below 2.3 × 10−4 when the two channels are operated simultaneously. [ABSTRACT FROM AUTHOR]

Featured Application: Optical interconnects for data centers. The rapid increase in total transmission capacity within and between data centers requires the construction of low-cost, high-capacity optical transmitters. Since a tremendous number of transmitters are required, photonic integrated circuits (PICs) using Si photonics technology enabling the integration of various functional devices on a single chip is a promising solution. A limitation of a Si-based PIC is the lack of an efficient light source due to the indirect bandgap of Si; therefore, hybrid integration technology of III-V semiconductor lasers on Si is desirable. The major challenges are that heterogeneous integration of III-V materials on Si induces the formation of dislocation at high process temperature; thus, the epitaxial regrowth process is difficult to apply. This paper reviews the evaluations conducted on our epitaxial growth technique using a directly bonded III-V membrane layer on a Si substrate. This technique enables epitaxial growth without the fundamental difficulties associated with lattice mismatch or anti-phase boundaries. In addition, crystal degradation correlating with the difference in thermal expansion is eliminated by keeping the total III-V layer thickness thinner than ~350 nm. As a result, various III-V photonic-device-fabrication technologies, such as buried regrowth, butt-joint regrowth, and selective area growth, can be applicable on the Si-photonics platform. We demonstrated the growth of indium-gallium-aluminum arsenide (InGaAlAs) multi-quantum wells (MQWs) and fabrication of lasers that exhibit >25 Gbit/s direct modulation with low energy cost. In addition, selective-area growth that enables the full O-band bandgap control of the MQW layer over the 150-nm range was demonstrated. We also fabricated indium-gallium-arsenide phosphide (InGaAsP) based phase modulators integrated with a distributed feedback laser. Therefore, the directly bonded III-V-on-Si substrate platform paves the way to manufacturing hybrid PICs for future data-center networks. [ABSTRACT FROM AUTHOR]

We demonstrate DML-based net 325-Gb/s at back-to-back and 321.24-Gb/s after 2-km standard single-mode fiber transmissions for >300-Gbps/λ short-reach optical interconnects. Our net rate performance denotes an increase of ∼34% compared to our previous works, while the pre-FEC rates are >400 Gbps. The DML transmitter is based on a PPR-enhanced, >100-GHz-bandwidth DML, fabricated by our novel membrane-III-V-on-SiC technology. Also wide-band, entropy-loaded DMT modulation is utilized based on a novel adaptive algorithm and via a digitally-preprocessed analog multiplexer. These results pave the way towards low-cost and energy-efficient Terabit Ethernet and a significant step towards achieving DML-based 400-Gbps/λ IM/DD systems in the future. [ABSTRACT FROM AUTHOR]

Increasing the modulation speed of semiconductor lasers has attracted much attention from the viewpoint of both physics and the applications of lasers. Here we propose a membrane distributed reflector laser on a low-refractive-index and high-thermal-conductivity silicon carbide substrate that overcomes the modulation bandwidth limit. The laser features a high modulation efficiency because of its large optical confinement in the active region and small differential gain reduction at a high injection current density. We achieve a 42 GHz relaxation oscillation frequency by using a laser with a 50-μm-long active region. The cavity, designed to have a short photon lifetime, suppresses the damping effect while keeping the threshold carrier density low, resulting in a 60 GHz intrinsic 3 dB bandwidth (f3dB). By employing the photon–photon resonance at 95 GHz due to optical feedback from an integrated output waveguide, we achieve an f3dB of 108 GHz and demonstrate 256 Gbit s−1 four-level pulse-amplitude modulations with a 475 fJ bit−1 energy cost of the direct-current electrical input. Directly modulated membrane distributed reflector lasers are fabricated on a silicon carbide platform. The 3 dB bandwidth, four-level pulse-amplitude modulation speed and operating energy for transmitting one bit are 108 GHz, 256 Gbit s−1 and 475 fJ, respectively. [ABSTRACT FROM AUTHOR]

Membrane buried-heterostructure III-V/Si distributed feedback (DFB) lasers with a stopband-modulated cavity on a Si substrate have been developed. The membrane III-V layers with 230-nm thickness enable us to construct an optical supermode with a 220-nm-thick Si waveguide that is used in standard Si photonics platform. We employ a uniform grating and Si waveguide, in which Si waveguide width is modulated to control the center wavelength of the stopband. The cavity can be designed by controlling the modulation width and modulation length of Si waveguide. Therefore, it is easy to engineer and fabricate the laser cavity compared with the cavity using λ/4-phase shift grating. Output light from the cavity is coupled to Si waveguide through InP inverse taper waveguide, and then coupled to SiOx waveguide through Si inverse taper waveguide, which provides the 2-dB fiber coupling loss. We have demonstrated single-mode lasing by using Si waveguide, where its width is increased 80 nm at the center of the cavity. The threshold current and maximum fiber output power are 3 mA and 4 mW, respectively. By extending the active region length to 1 mm, 17-mW fiber coupled output power is obtained. High-temperature operation up to 130 °C is also obtained with a 1-mW fiber output power. [ABSTRACT FROM AUTHOR]

A high-efficiency Mach-Zehnder modulator (MZM) using InGaAsP phase shifters and a semiconductor optical amplifier (SOA) using multiple-quantum-well (MQW) are integrated on Si-waveguide circuits. Membrane structure is easy to optically couple to the widely-used 220-nm-thick Si waveguides, because both layers have comparable effective refractive indices. To integrate different bandgap III-V compound semiconductors; InGaAsP-based MQW for SOA and InGaAsP bulk for MZM, we employ epitaxial regrowth on thin-InP layer that is directly bonded on a silicon-on-insulator (SOI) wafer. Their thicknesses are smaller than the critical thickness (∼430 nm) for epitaxial growth of the InP-based layers bonded on the SOI wafer. This fabrication procedure is beneficial for the wafer-level integration of InP-based devices with different bandgaps on Si-photonic circuits. Furthermore, membrane lateral p-n and p-i-n diode structures improve the modulation efficiency of the MZM and reduce the power consumption of the SOA due to the high optical confinement factor and small active area. The integrated 300-μm-long SOA and MZM with 500-μm-long phase shifters show a fiber-to-fiber lossless operation with the SOA current of only 24 mA at room temperature. The modulation efficiency of the compact MZM is high enough for eye opening with non-return-to-zero (NRZ) signals from 28 to 40 Gbit/s. By using the SOA to amplify the signals modulated by the MZM, the fiber output power of −3.4 dBm was obtained without any significant pattern effect. [ABSTRACT FROM AUTHOR]

We demonstrate a high signal-to-noise ratio (SNR) for a photonic-crystal nanophotodetector (PD). The ultralow-capacitance nano-PD can be terminated with a load resistor with a resistance as high as 59 kΩ for efficient light-to-voltage conversion, and its strong thermal-noise suppression leads to an SNR that is 30 dB higher than that of the conventional p-i-n PD terminated with a 50-Ω load. The noise equivalent power is only 500 fW/√Hz, while a gigahertz-level bandwidth can be maintained when considering that the PD capacitance is only 1 fF. Theoretically, this allows optical reception at less than 100 aJ to obtain a bit error rate of 10–9. The resistor-loaded nano-PD requires a small electrical biasing energy comparable to the optical energy, which is remarkably energy saving compared with avalanche PDs or other PDs integrated with amplifiers. Such a receiver promises a dense optical interface with CMOS electronics in photonic networking and processing chips. [ABSTRACT FROM AUTHOR]

The introduction of photonic technologies into mature electronic circuits is in high demand to accelerate on-chip information networking and even computing. Great difficulty lies in the fact that the optoelectronic coupling at their interfaces requires a substantial charging energy determined by their capacitance. Optoelectronic devices have been too large to reduce the integrated capacitance down to the femtofarad scale. Here we use a photonic-crystal platform to demonstrate the first experimental proof of optoelectronic integration at only 2 fF. This allows us to realize a record-low attojoule-energy electro-optic modulator (an electrical-to-optical or E–O converter) and an amplifier-free photoreceiver (an optical-to-electrical, or O–E converter), which leads to ultralow-energy signal conversion. By integrating these O–E/E–O devices, we demonstrate femtofarad 'O–E–O transistors' with optical signal gain that show various optical nonlinear functions, including as all-optical switches, wavelength converters and cascadable optical repeaters with a femtojoule-per-bit energy consumption. These femtofarad-scale O–E/E–O/O–E–O devices promise tightly coupled photonic–electronic integration for new fields of energy-saving information processing. A photonic-crystal platform enables attojoule-energy electro-optic modulators and amplifier-free photoreceivers. [ABSTRACT FROM AUTHOR]

We report on space-division multiplexing (SDM) transmissions of up to 400 Gb/s over a homogeneous four-core fiber using discrete multitone (DMT) modulation for intra-datacenter applications and 200/400 GbE links. The transmission system is enabled by a compact, SDM-channel scalable, multi-core fiber (MCF) pluggable, and energy-efficient SDM transmitter composed of a 4-channel 1.3-μm membrane directly modulated laser (DML) array-on-silicon integrated with a fiber-bundle type fan-in with loss of less than 1 dB and negligible optical and electrical crosstalk (XT). By simultaneously modulating all four lasers, 200-Gb/s (50-Gb/s/channel) and 400-Gb/s (100-Gb/s/channel) are achieved over a 425-m MCF link for KP4 and soft-decision forward error correction, respectively, with a power reduction of ∼6× compared with conventional DML transmitters. Additionally, numerical simulations based on a detailed rate-equations model predict the feasibility of the system for MCF transmissions up to 10 km even with moderate levels of XT. [ABSTRACT FROM AUTHOR]

We describe a new multicore fiber (MCF) receptacle for space division multiplexing (SDM) based transceiver applications, in which we integrated a compact fiber-bundle type fan-in/fan-out device for directly connecting MCF to LDs and PDs. We design the length of the fan-out fibers taking their bending stress into account to achieve a configuration with a smaller footprint. With the proposed receptacle, we develop a 100 Gb/s SDM transmitter based on a four-channel, 1.3 μm membrane laser array on Si, in which spot-size convertor (SSC) using inverse taper InP and SiON waveguides is integrated. Since the core size of SiON waveguide is much smaller than that of MCF, we utilize different fibers with optimized modal fields at each connection point and introduce thermally-expanded-core (TEC) fusion splicing to realize a low-loss connection between them. We achieve a pluggable connection between the lasers and 125 μm-cladding 4-core MCF in an LC connector. The developed receptacle maintained satisfactory laser characteristics including sufficient output power and clear eye openings for directly modulated 28 Gb/s NRZ signals. We also achieve an error-free transmission at a bit-error rate of less than 10−12 with a 500-m MCF transmission link for all 4 channels with simultaneous 4-channel operation. [ABSTRACT FROM AUTHOR]

Generally, reverse-biased photodetectors (PDs) are used for high-speed optical receivers. The forward voltage region is only utilized in solar-cells, and this photovoltaic operation would not be concurrently obtained with high efficiency and high speed operation. Here we report that photonic-crystal waveguide PDs enable forward-biased high-speed operation at 40 Gbit/s with keeping high responsivity (0.88 A/W). Within our knowledge, this is the first demonstration of the forward-biased PDs with high responsivity. This achievement is attributed to the ultracompactness of our PD and the strong light confinement within the absorber and depleted regions, thereby enabling efficient photo-carrier generation and fast extraction. This result indicates that it is possible to construct a high-speed and ultracompact photo-receiver without an electrical amplifier nor an external bias circuit. Since there is no electrical energy required, our estimation shows that the consumption energy is just the optical energy of the injected signal pulse which is about 1 fJ/bit. Hence, it will lead to an ultimately efficient and highly integrable optical-to-electrical converter in a chip, which will be a key ingredient for dense nanophotonic communication and processors. [ABSTRACT FROM AUTHOR]

Demand for more transmission capacity in data centres is increasing due to the continuous growth of Internet traffic. The introduction of external modulators into datacom networks is essential with advanced modulation formats. However, the large footprint of silicon photonics Mach-Zehnder (MZ) modulators will limit further increases in transmission capacity. To overcome this, we introduce III-V compound semiconductors because the large electron-induced refractive-index change, high electron mobility and low carrier-plasma absorption are beneficial for overcoming the trade-offs among the voltage-length product (VπL), operation speed and insertion loss of Si MZ modulators. Here, we demonstrate an MZ modulator with a 250-µm-long InGaAsP/Si metal-oxide-semiconductor (MOS) capacitor phase-shifter and obtain a VπL of 0.09 Vcm in accumulation mode, an insertion loss of ∼1.0 dB, a cutoff frequency of ∼2.2 GHz in depletion mode and a 32-Gbit s-1 modulation with signal pre-emphasis. These results are promising for fabricating high-capacity large-scale photonic integrated circuits with low power consumption. [ABSTRACT FROM AUTHOR]

We report novel high-bandwidth InP-based Mach–Zehnder modulator and in-phase/quadrature (IQ) modulators that we realized by combining an n-i-p-n heterostructure and a capacitively loaded traveling wave electrode. The extremely low electrical and optical loss structure enhances the 3-dB electro-optic bandwidth of over 67 GHz without degrading other properties such as driving voltage and optical loss. The modulator also exhibits a static extinction ratio of over 24 dB with a Vπ of less than 1.5 V for the entire C-band. Furthermore, we demonstrate the first 120-Gbaud rate IQ modulation without optical pre equalization, and 100-Gb/s non-return-to-zero on-off keying modulation with a dynamic extinction ratio of over 10 dB. [ABSTRACT FROM PUBLISHER]

The authors have developed a new heterogeneous‐integration method for fabricating semiconductor lasers with high modulation efficiency on Si substrates. The method employs the direct bonding of an InP‐based active layer to the SiO2 layer of a thermally oxidised Si substrate (SiO2 /Si substrate), followed by the epitaxial growth of InP to form a buried heterostructure (BH). By using the InP membrane, the authors realise epitaxial growth of an InP on the InP membrane directly bonded to Si without crystal quality degradation. Both a theoretical estimation and photoluminescence measurements revealed that the total laser thickness must be less than the critical thickness determined by the applied thermal strain. The authors confirmed that the crystal quality of the BH is comparable to that fabricated on an InP substrate when using a 250‐nm‐thick InP‐based membrane. A distributed feedback laser fabricated on a SiO2 /Si substrate exhibited continuous‐wave operation up to 100°C and was directly modulated by a 40 Gbit/s non‐return‐to‐zero signal with a bias current of 15 mA. These results indicate that epitaxial growth using a directly bonded InP‐based active layer on a SiO2 /Si substrate allows us to achieve lasers with high modulation efficiency and to use a large‐scale Si wafer as a fabrication platform, resulting in low‐cost fabrication. [ABSTRACT FROM AUTHOR]

Reducing the operating energy of a distributed feedback (DFB) laser is a critical issue if we are to use the device as a directly modulated light source employing wavelength division multiplexing technologies in short-distance datacom networks. A membrane buried heterostructure (BH) DFB laser on a SiO2 layer is one candidate for reducing the operating energy because it provides a strong carrier and optical confinement in the active region. For low-cost fabrication, we have proposed and developed a fabrication procedure that employs the buried growth of an InP layer by using a directly bonded InP-based active layer on a SiO2/Si substrate, which enables us to use a large-scale Si wafer. To overcome the problem of the difference between the thermal expansion coefficients of Si, SiO 2, and InP, we have used a thin active layer (∼250 nm) on a SiO2/Si substrate as a template for the epitaxial growth of a III–V compound semiconductor. A lateral current injection structure is essential for fabricating a device with a 250-nm-thick template. Our fabricated DFB laser with a 73-μm cavity length exhibits a threshold current of 0.9 mA for continuous operation at room temperature and achieves lasing at up to 100 °C. We have also demonstrated 171-fJ/bit operation with a 25.8-Gb/s NRZ signal. These results indicate that the BH DFB laser on a SiO2/Si substrate is highly suitable for use as a transmitter for datacom applications. [ABSTRACT FROM PUBLISHER]

Large-scale photonic integrated circuits (PICs) are essential for reducing the cost and power consumption of optical networks. Selective doping by means of thermal diffusion and ion implantation is suitable for fabricating PICs because it enables doping into desired regions without crystal growth. In this paper, we report the fabrication of a lateral-p-i-n-diode-structure electro-absorption modulator (EAM) integrated with a DFB (EADFB) laser. Owing to the lateral p-i-n structure, we are able to use the broadening of the exciton absorption peak that occurs when the electric field is applied parallel to the quantum well. By comparing the calculated absorption spectrum change for parallel and vertical electric fields, we found that it occurs with a low electrical field, although the amount of absorption coefficient change is small for the parallel one. Thus, in our design, we make the EAM length larger than that of the conventional vertical electric field EAM. However, because of the low parasitic capacitance of the lateral EAM, we can expect to achieve high-speed operation. With a fabricated device with a 200-μm-long EAM, we have achieved 50-Gb/s operation with clear eye opening. We have also achieved a side-mode suppression ratio of more than 50 dB by using a surface grating. These results indicate that our lateral EADFB laser is very promising as an integrated light source for large-scale PICs and that our fabrication process based on selective doping is suitable for them. [ABSTRACT FROM PUBLISHER]

Lasers with ultra-low operating energy are desired for use in chip-to-chip and on-chip optical interconnects. If we are to reduce the operating energy, we must reduce the active volume. Therefore, a photonic crystal (PhC) laser with a wavelength-scale cavity has attracted a lot of attention because a PhC provides a large Q-factor with a small volume. To improve this device's performance, we employ an embedded active region structure in which the wavelength-scale active region is buried with an InP PhC slab. This structure enables us to achieve effective confinement of both carriers and photons, and to improve the thermal resistance of the device. Thus, we have obtained a large external differential quantum efficiency of 55% and an output power of −10 dBm by optical pumping. For electrical pumping, we use a lateral p–i–n structure that employs Zn diffusion and Si ion implantation for p-type and n-type doping, respectively. We have achieved room-temperature continuous-wave operation with a threshold current of 7.8 µA and a maximum 3 dB bandwidth of 16.2 GHz. The results of an experimental bit error rate measurement with a 10 Gbit s−1 NRZ signal reveal the minimum operating energy for transferring a single bit of 5.5 fJ. These results show the potential of this laser to be used for very short reach interconnects. We also describe the optimal design of cavity quality (Q) factor in terms of achieving a large output power with a low operating energy using a calculation based on rate equations. When we assume an internal absorption loss of 20 cm−1, the optimized coupling Q-factor is 2000. [ABSTRACT FROM AUTHOR]

We have developed a novel nanoscale temperature-measurement method using fluorescence in the near-field called Fluorescence Near-field Optics Thermal Nanoscopy (Fluor-NOTN). Fluor-NOTN enables the temperature distributions of nanoscale materials to be measured in vivo/in situ. The proposed method measures temperature by detecting the temperature dependent fluorescence lifetimes of Cd/Se Quantum Dots (QDs). For a high-sensitivity temperature measurement, the auto-fluorescence generated from a fiber probe should be reduced. In order to decrease the noise, we have fabricated a novel near-field optical-fiber probe by fusion-splicing a photonic crystal fiber (PCF) and a conventional single-mode fiber (SMF). The validity of the novel fiber probe was assessed experimentally by evaluating the auto-fluorescence spectra of the PCF. Due to the decrease of auto-fluorescence, a six- to ten-fold increase of S/N in the near-field fluorescence lifetime detection was achieved with the newly fabricated fusion-spliced near-field optical fiber probe. Additionally, the near-field fluorescence lifetime of the quantum dots was successfully measured by the fabricated fusion-spliced near-field optical fiber probe at room temperature, and was estimated to be 10.0 ns. [ABSTRACT FROM AUTHOR]

Another way to confirm the mistake is by noticing that, if 2T 16.67 ps was assumed, that should have corresponded to a symbol rate of 120 GBaud (instead of 60 GBaud). The mistake was in the x-axis of the shown eye diagrams, and it was due to a coding error in the MATLAB plotting function that was used. Graph: Figure 5 60 GBaud PAM-4 signal evaluation: (a) Experimental setup; (b) Bit-error rate (BER) versus received optical power at back-to-back (BTB) and after 2-km SSMF transmissions, and (c,d) Eye diagrams after equalization. [Extracted from the article]

Near-future upgrades of intra data center networks and high-performance computing systems would require optical interconnects capable of operating at beyond 100 Gbps/lane. In order for this evolution to be achieved in a sustainable way, high-speed yet energy-efficient transceivers are in need. Towards this direction we have previously demonstrated directly-modulated lasers (DMLs) capable of operating at 50 Gbps/lane with sub-pJ/bit efficiencies based on our novel membrane-III-V-on-Si technology. However, there exists an inherent tradeoff between modulation speed and power consumption due to the carrier-photon dynamics in DMLs. In this work, we alleviate this tradeoff by introducing photon–photon resonance dynamics in our energy-efficient membrane DMLs-on-Si design and demonstrate a device with a maximum 3-dB bandwidth of 47.5 GHz. This denotes a bandwidth increase of more than 2x times compared to our previous membrane DMLs-on-Si. Moreover, the DML is capable of delivering 60-GBaud PAM-4 signals under Ethernet's KP4-FEC threshold (net data rate of 113.42 Gbps) over 2-km of standard single-mode fiber transmission. DC energy-efficiencies of 0.17 pJ/bit at 25 °C and 0.34 pJ/bit at 50 °C have been achieved for the > 100-Gbps signals. Deploying such DMLs in an integrated multichannel transceiver should ensure a smooth evolution towards Terabit-class Ethernet links and on-board optics subsystems. [ABSTRACT FROM AUTHOR]