32  Gbps heterogeneously integrated quantum dot waveguide avalanche photodiodes on silicon

Abstract

We report a heterogeneous GaAs-based quantum dot (QD) avalanche photodiode (APD) on silicon with an ultralow dark current of 10 pA at − 1 V , 3 dB bandwidth of 20 GHz and record gain-bandwidth product (GBP) of 585 GHz. Furthermore, open eye diagrams up to 32 Gb/s are demonstrated at 1310 nm. The k-factor has been measured for these devices to be as low as 0.14. A polarization dependence on gain and bandwidth has been observed and investigated. This shows the potential to integrate a high-speed receiver in a wavelength division multiplexing (WDM) system on a QD-based silicon photonics platform.

An Energy-Efficient and Bandwidth-Scalable DWDM Heterogeneous Silicon Photonics Integration Platform

“…9(a) exhibits the static performance of a 3 µm×30 µm device. The dark current density as low as 3.3×10 -7 A/cm 2 from 10 pA dark current at -1 V bias is among the lowest dark current ever reported for a III-V-on-Si PD [89]. Such low dark current was also observed in the monolithic InAs QD PDs [91].…”

“…9(b)). Bandwidth started decreasing under higher bias voltage due to longer avalanche buildup time, but gain-bandwidth product (GBP) reached a record-high value of 585 among all reported QD APDs to our best knowledge [89]. Higher GBP for TM-polarized light input is expected owing to even higher TM gain.…”

“…In our case co-integration of GaAs-based QD optical gain material and InP-based InGaAs detector material certainly will make the fabrication more challenging due to two different III-V material systems. Fortunately, high-performance waveguide-type QD APDs based on the identical QD laser/SOA epitaxial structure were developed recently to avoid any fabrication overhead associated with new III-V material involvement [89,90].…”

Demonstration of a 17 × 25 Gb/s Heterogeneous III-V/Si DWDM Transmitter based on (De-) Interleaved Quantum Dot Optical Frequency Combs

“…To address the aforementioned issues, at Hewlett Packard Labs, we are developing a novel heterogeneous III-V/Si dense wavelength division multiplexing (DWDM) architecture to address chip power consumption (< 1.5 pJ/bit) and increased transmission bandwidth (> 1 Tb/s) [6]- [8]. The heterogeneous platform described in this work has shown the technical capability and fabrication compatibility to integrate all building blocks, such as heterogeneous quantum dot (QD) optical frequency comb (OFC) laser sources [6], [9]- [14], wavelength (de-) interleavers [15], [16], micro-ring modulators (MRRs) [8], [17]- [19], photodetectors (PDs) [20]- [23], and semiconductor optical amplifiers (SOAs) [24] to form a space division multiplexing (SDM)-DWDM transceiver as shown in Fig. 1 [6], [7].…”

“…[7] 2 > REPLACE THIS LINE WITH YOUR MANUSCRIPT ID NUMBER (DOUBLE-CLICK HERE TO EDIT) < On-chip wavelength (de-)interleavers solve this problem by spatially dividing even and odd numbered OFC frequencies onto separate waveguides [16], [27], [28]. For our architecture, each waveguide will have a half number (10) of the total MRR count (20), but with the channel spacing doubled. By cascading more low-loss (de-)interleavers in series, more spatial channels and wider channel spacing is possible, allowing to use a comb source with tens or hundreds of comb lines but with smaller channel spacing [8].…”