Initially, we’ll discuss an SOI based, carrier injection micro-ring modulator. The static optical and electrical characteristics of this device will be reviewed and described. Thermal control and modulation mechanisms with pre-emphasis will be outlined. Automated wafer-lever optical/electrical results from volume foundries (Leti and STMicro) used for PDK/Verilog model development will be reviewed, along with experimental data on direct modulation to 25 Gb/s, crosstalk at various DWDM channel separations, and demonstrations with an external quantum-dot based comb laser with 80 and 50GHz channel spacing.
Following this, our work on directly modulated hybrid quantum-well ring lasers will be reviewed in design, fabrication. Experimental results for modulation at 12.5 Gb/s/channel, integration with MOS capacitor for wavelength control and modulation and a thermal shunt for temperature management will highlight the advantages of this technology that may be exploited. Subsequently, our work on hybrid quantum-dot based comb lasers for on-chip DWDM sources will be discussed in their details of physical operation, demonstrating successful mode-locking and noise-free operation across the 20-80C thermal range. Our work on the integration of on-chip APDs from a CMOS-compatible processes will also be reviewed, demonstrating error-free operation at 12.5 Gb/s and 25 Gb/s with a sensitivity of -26dBm and -16dBm, respectively. The use of APDs will drastically decrease the overall power consumption of the interconnect, lowering total cost of ownership. Finally, our most recent progress on integration of the silicon photonics with CMOS by a flip-chip will be reviewed showing high-speed modulation and thermal control for a multi-channel DWDM transceiver.
The negatively-charged nitrogen-vacancy centers in diamond has motivated many groups building scalable quantum information processors based on diamond photonics. This is owning to the long-lived electronic spin coherence and the capability for spin manipulation and readout of NV centers.<sup>1-4</sup> The primitive operation is to create entanglement between two NV centers, based on schemes such as 'atom-photon entanglement' proposed by Cabrillo <i>et al</i>.<sup>5</sup>To scale this type of scheme beyond two qubits, one important component is an optical switch that allows light emitted from a particular device to be routed to multiple locations. With such a switch, one has choices of routing photons to specified paths and has the benefit of improving the entanglement speed by entangling multiple qubits at the same time. Yield of the existing diamond cavities coupled with NV centers are inevitably low, due to the nature of randomness for NV placement and orientation, variation of spectral stability, and variation of cavity resonance frequency and quality factor. An optical switch provides the capability to tolerate a large fraction of defective devices by routing only to the working devices. Many type of switching devices were built on conventional semiconductor materials with mechanisms from mechanical, thermal switching to carrier injection, photonics crystal, and polymer refractive index tuning .<sup>6-8</sup> In this paper, we build an optical-thermal switch on diamond with micro-ring waveguides, mainly for the simplicity of the diamond fabrication. The the switching function was realized by locally tuning the temperature of the diamond waveguides. Switching efficiency of 31% at 'drop' port and 73% at 'through' port were obtained.
We demonstrate coupling between the zero phonon line (ZPL) of nitrogen-vacancy centers in diamond and the
modes of optical micro-resonators fabricated in single crystal diamond membranes sitting on a silicon dioxide
substrate. A more than ten-fold enhancement of the ZPL is estimated by measuring the modification of the
spontaneous emission lifetime. The cavity-coupled ZPL emission was further coupled into on-chip waveguides
thus demonstrating the potential to build optical quantum networks in this diamond on insulator platform.