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A mode-multiplexed transmitter combining a 2-D VCSEL matrix on a Si interposer and a multi-plane light converter is demonstrated. This enables 200-Gb/s transmission using 10G-class VCSELs over 100-m multimode fiber with direct detection and 28-km few-mode fiber with coherent detection.

In this paper, based on a wet etched silicon interposer, we propose a 2.5D assembly of two dimensional optical transceivers for 400 Gbps parallel optical interconnections. In this opto-electronic packaging, two dimensional optical matrix is formed as 250 μm in both the x -and y-directions by exploiting commercial opto-electronic arrays, and a compact optical interface is used to couple the light channels with fiber ribbons. Each quadrant of the optical matrix is connected with its CMOS IC part via impedance matched co-planner wave guides. The shortest traces between optics and CMOS ICs can be 300 μm, benefiting from flip-chip technology. The process flow of silicon interposer fabrication is illustrated. With flip-chip bonding, 25 Gbps 2D 16-channel receiver is assembled on the silicon interposer, and the sub-module, including the optical interface, is scaled down to 4 mm by 6 mm. In addition, the performance of this assembled module is fully characterized. Uniform and clear eye patterns are captured for all of the channels. Receiver sensitivities are also tested for all channels at 25.78 Gbps, 2 31-1 PRBS, with the variation less than 1.5 dB at error free operation.

We experimentally demonstrate the control over the emission of quantum dots embedded in photonic molecules via mode field modulation. By locally changing the cavity frequencies we control, and even suppress, spontaneous emission.

High bandwidth density on-board optical transmitter is reported in this paper. This on-board transmitter contains 4×12-channel 10Gbps CMOS driver ICs and 4×12-channel 850nm Multimode (MM) VCSEL arrays, with a total 48×10Gbps bandwidth and is packaged through flip-chip bonding on a flexible printed circuit (FPC) with SnAg solder bumps. Due to the compact package design, based on a commercial 1mm pitch ISI HoLi pin grid array (PGA) connector, the size of FPC is only 31.5mm × 31.5mm and it offers a state-of-art bandwidth density of 0.483Gbps/mm2. Investigation of RF signal propagation on the FPC is carried out for design validation at 10Gbps and to further explore the potential of the suggested platform differential pairs are simulated up to 30Gbps. An optical straight lens connector is used to couple the light to a single 48 fibers MT connector. To validate the design concept the fully assembled transmitter is tested at 10Gbps. Bit error rates for all 48 channels at 10Gbps as well as eye diagrams for few representative channels are reported.

We propose and theoretically investigate a new type of atom-phonon interaction in an optomechanical system. The interaction strength is controlled by the intensity of the intra-cavity optical field. We discuss relevant designs and possible applications.

In this paper, we demonstrate a way of packaging CMOS ICs and optoelectronics, which has been achieved by using a deeply wet etched silicon interposer. The silicon interposer concept is used for the assembly of electronics (drivers, TIAs), photonics (VCSELs, PDs) and mechanical optical interface (MOI) and can be fabricated on full wafers. Only four steps of lithography are needed to fabricate the silicon interposer and both sides of this interposer are utilized for electrical and optical connections. The impedance matched metal traces and gold bumps for electrical connection are lithographically transferred and electro-plated. The optical vias are also opened by wet etching. The process is performed on a diced 1 inch silicon wafer, 4 interposers are made with one process flow. The obtained silicon interposers are used for 12 × 10G transmitter and 4 × 25G transceiver. The process challenges for the 3D patterning of the silicon interposer and for the metal traces definition are discussed. Data integrity experiments are performed.

Using a pump-probe differential transmission experiment in heterodyne detection, we measured the refractive index dynamics at the ground-state excitonic transition in electrically pumped InAs/GaAs quantum-dot amplifiers emitting near 1.3 µm at room temperature. We compare three samples differing only in the level of p-doping, and interpret the measured index changes taking into account the gain dynamics in these devices. We find that in absorption, the excess hole density due to p-doping accelerates the recovery and reduces the refractive index change, since filling of the hole states by p-doping shifts the induced changes in the hole population toward high energy states. Conversely, in gain, the reduced electron reservoir in the excited states in p-doped devices results in slower gain recovery dynamics and in larger refractive index changes compared to undoped devices operating at the same modal gain. The linewidth enhancement factor inferred from these measurements shows that p-doping is effective in reducing this parameter mainly due to the larger differential gain in p-doped devices in the gain regime. © 2009 IEEE.

2.5D silicon interposer, for a cost effective optoelectronic package, is proposed and fabricated on a wafer level. Using this packaging approach, the fully assembled 120 Gb/s transmitter is scaled down to 6mm × 7mm.

Semiconductor nanolasers provide an attractive route towards high density photonic integrated circuits in low power applications such as optical interconnects. In this paper we present the concept of a waveguide-coupled nanolaser for integration in a CMOS compatible photonic platform. We exploit metallic and dielectric confinement to provide high quality factors exceeding 500 in a wavelength-scale cavity, that provides efficient cooling and cross-talk immunity due to the metal coverage. We present simulations detailing the design considerations for high quality factors and efficient waveguide coupling. Optical and electrical simulations predict room temperature operation at 1.55 µm with a threshold current of 120 µA and a differential quantum efficiency of 0.16. We also discuss briefly the challenges of fabricating these devices and integrating them in the photonic platform.

Study of subwavelength optical phenomena has taken an increasing importance in the past few years. Near- field scanning optical microscopy (NSOM) is the usual solution for optical sensing below the diffraction limit. It consists in coupling light in a fiber through a nanoscale hole and detecting it with a conventional detector. A better optimized method would be to make the detector itself nanoscale. The dark count rate being usually proportional to the active area, this would greatly enhance the signal to noise ratio. The paper proposed a detector that has nanoscale dimensions, nanosecond response time and single or multiphoton sensitivity.

Local post-production processing of single holes in a planar photonic crystal is demonstrated by selectively opening a masking layer by focused ion beam milling. Local tuning was optically demonstrated by both blue-shifting and subsequent red-shifting the resonance frequency of a point defect cavity. Since only a few holes of the PC are affected by the post-processing, the Q-factor is not significantly changed. This method can be applied to precisely control the resonant frequency, and can also be used for mode selective tuning.

InAs quantum dots emitting at 1.3 Jµm and located inside a photonic crystal membrane nanocavity are studied by electrical pumping. An increase of the recombination rate is observed for quantum dots in resonance with the cavity mode.

Field-dependent photo-current measurements in Quantum Rod systems show that the orientation of the permanent dipole moment of a standard GaAs/InAs quantum dot can be reversed by fabricating high-aspect ratio Quantum Rod systems. ©2008 IEEE.

Date of Conference: 17-22 June 2007 The low voltage modulation in InAs quantum dot waveguides is observed in this paper. We have measured the electro-optic coefficient in multilayer quantum dot structures far away from resonance and obtained an enhancement compared to bulk GaAs. Electro-absorption measurement results suggest that these waveguides are good candidates for use in electro-absorption modulators such as Mach-Zehnder devices.