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We report on an eight-node 10 Gb/s experimental test-bed for data center networking. Preliminary experimental results show that by using optical wavelength switching routing, this system can support high-capacity, low-latency and contention-less error-free communication between the eight nodes.

We demonstrate a fully reconfigurable 125 GHz flat passband silicon photonic interleaver with a box-like spectral response and 20 dB extinction ratio.

We present a fully-reconfigurable CMOS-compatible silicon-photonic lattice-filter with four cascaded unit cells consisting of resonant rings and Mach-Zehnder interferometers. The measurements show high-quality filter responses including IIR and FIR filter characteristics matching theoretical predictions.

We design, fabricate, and demonstrate a silicon nitride (Si(3)N(4)) multilayer platform optimized for low-loss and compact multilayer photonic integrated circuits. The designed platform, with 200 nm thick waveguide core and 700 nm interlayer gap, is compatible for active thermal tuning and applicable to realizing compact photonic devices such as arrayed waveguide gratings (AWGs). We achieve ultra-low loss vertical couplers with 0.01 dB coupling loss, multilayer crossing loss of 0.167 dB at 90° crossing angle, 50 μm bending radius, 100 × 2 μm(2) footprint, lateral misalignment tolerance up to 400 nm, and less than -52 dB interlayer crosstalk at 1550 nm wavelength. Based on the designed platform, we demonstrate a 27 × 32 × 2 multilayer star coupler.

We present the design, fabrication and characterization of athermal nano-photonic silicon ring modulators. The athermalization method employs compensation of the silicon core thermo-optic contribution with that from the amorphous titanium dioxide (a-TiO(2)) overcladding with a negative thermo-optic coefficient. We developed a new CMOS-compatible fabrication process involving low temperature RF magnetron sputtering of high-density and low-loss a-TiO(2) that can withstand subsequent elevated-temperature CMOS processes. Silicon ring resonators with 275 nm wide rib waveguide clad with a-TiO(2) showed near complete athermalization and moderate optical losses. Small-signal testing of the micro-resonator modulators showed high extinction ratio and gigahertz bandwidth.

This paper demonstrates a rapid and full hitless defragmentation method in elastic optical networks exploiting a new technique for fast wavelength tracking in coherent receivers. This technique can be applied to a single-carrier connection or each of the subcarriers forming a super-channel. A proof-of-concept demonstration shows hitless defragmentation of a 10 Gb/s QPSK single-carrier connection from 1547.75 nm to 1550.1 nm in less than 1 µs. This was obtained using a small (0.625 kB) link-layer transmitter buffer without the need for any additional transponder. We also demonstrated that the proposed defragmentation technique is capable of hopping over an existing connection, i.e. 10 Gb/s OOK at 1548.5 nm, without causing any degradation of its real-time Bit Error Rate (BER) value. The proposed scheme gives advantages in terms of overall network blocking probability reduction up to a factor of 40.

This Letter demonstrates a measurement technique based on frequency-to-time mapping and coherent detection, which enables the complete (i.e., amplitude and phase) characterization of dynamically reconfigurable photonic filters. We apply this technique to a unit cell from a silicon CMOS-compatible photonic lattice filter that has a rapidly changing transfer function with an 8.33 ns update time, 120 MHz spectral resolution, and 12 GHz bandwidth. These dynamic measurements allow characterization of transients, thermal effects, filter fidelity, and other time-dependent phenomena during switching.

We demonstrate static and dynamic optical arbitrary waveform generation in a heterogeneously integrated Si3N4 AWG-InP modulator array-Si3N4 AWG chip-scale module. High contrast Si3N4 AWGs and nearly pure phase InP modulation provided high fidelity OAWG.

We demonstrate elasticity in time, frequency and space domains for an optical link at 960-Gb/s with 6.4-b/s/Hz spectral efficiency. Modulation format and number of spatial modes are selected based on Shannon's Law and crosstalk-dependent impairments.

We transmit over all 30 spatial and polarization modes of a 22.8-km multimode fiber. 15-mode photonic lanterns enabled low-loss coupling into and out of the fiber and a time-multiplexed coherent receiver facilitates measurement of all 30 signals.

This paper presents a rapid laser wavelength stabilization and monitoring technique based on a feedback loop using AWG with PD arrays at 0.5 MHz. The experiment demonstrates control accuracy of ±0.015 nm on microsecond timescale.

We demonstrate 12 x 12 multiple-input multiple-output mode multiplexed transmission over130-km of few-mode fiber of a combined 6-space-, 2-polarization-, and 8-wavelength-division multiplex, using low-loss photonic lantern and 3D-waveguide mode multiplexers.

This paper demonstrates simultaneous defragmentation of two channels without causing errors (BER

We demonstrate orbital angular momentum state conversion using two 3D photonic integrated circuits for free-space communication of 20-Gb/s QPSK signals. Different combinations of OAM states show error-free performance with 379,960 bits tested.

We demonstrate a silicon photonics coherent transceiver in a ball-grid-array package. It can be handled like a conventional surface-mount-technology component, surviving pick-and-place and 260° C reflow. It saves cost, size and provides enhanced thermals and bandwidth.

We demonstrate a hybrid integrated optical phased array (OPA) based on a 2D photonic integrated circuit and 3D waveguides. The 4×4 OPA supports 4.93° horizontal and vertical beam steering near 1550 nm with 7.1-dB loss.