Monolithic integration of a phase noise based quantum random number generator on InP platform

We present the experimental characterization of a fully integrated InP-based quantum random number generator chip composed from a single gain switched DBR laser and two Mach Zehnder interferometers. We demonstrate high degree of randomness by testing the QRNG output in the NIST Statistical Test Suite

480 Gbps WDM Transmission Through an Al2O3:Er3+ Waveguide Amplifier

The increasing need for more efficient communication networks has been the main driving force for the development of complex photonic integration circuits combining active and passive building blocks towards advanced functionality. However, this perpetual effort comes with the cost of additive power losses and the research community has resorted to the investigation of different materials to establish efficient on chip amplification. Among the different proposals, erbium doped waveguide amplifiers appear to be a promising solution for high performance transmission in the C-band band with low fabrication cost, due to their CMOS compatibility and integration potential with the silicon\silicon nitride photonic platforms. In this paper we provide a holistic study for high-speed WDM transmission capabilities of a monolithically integrated Al2O3:Er3+ spiral waveguide amplifier co-integrated with Si3N4 components, providing a static characterization and a dynamic evaluation for (a) 440 Gbps, (b) 840 Gbps and (c) 860 Gbps WDM transmissions achieving clearly open eye diagram in all cases. The active region of the erbium doped waveguide amplifier consists of a 5.9 cm Al2O3:Er3+ spiral adiabatically coupled to passive Si3N4 waveguides combined with on chip 980 nm/1550 nm WDM Multiplexers/Demultiplexers. Experimental results reveal bit error rate values below the KR4 FEC limit of 210-5 for all channels, without any DSP applied on the transmitter or receiver side for a 440 Gbps and 840 Gbps data stream transmission

Long term experimental verification of a single chip quantum random number generator fabricated on the InP platform

This work presents the results from the experimental evaluation of a quantum random number generator circuit over a period of 300 minutes based on a single chip fabricated on the InP platform. The circuit layout contains a gain switched laser diode (LD), followed by a balanced Mach Zehnder Interferometer for proper light power distribution to the two arms of an unbalanced MZI incorporating a 65.4 mm long spiral waveguide that translates the random phase fluctuations to power variations. The LD was gain-switched at 1.3 GHz and the chip delivered a min-entropy of 0.5875 per bit after removal of the classical noise, resulting a total aggregate bit rate of 6.11 Gbps. The recoded data set successfully passed the 15-battery test NIST statistical test suite for all data sets

Self-Stabilized 50 Gb/s Silicon Photonic Microring Modulator Using a Power-Independent and Calibration-Free Control Loop

This paper demonstrates the possibility of automatically stabilizing the working condition of an integrated Silicon Photonics microring modulator with a novel dithering-based control scheme. The proposed feedback strategy leverages a realtime acquisition of the modulator non-linear transfer function (TF) and operates by setting the target locking point to the zero of the TF second derivative, i.e. where the ring slope is maximum. This results in a control algorithm that is both power-independent and calibration-free. The paper shows that the operating point identified in this way has a negligible difference with respect to the optimum working condition of minimum Transmitter Penalty normally targeted and that the employed dithering signal does not affect the modulation quality. The control performances, made possible by an FPGA-based platform ensuring a 30 ms response time, are assessed in a 50 Gbit/s routing scenario, demonstrating effective compensation of wavelength and thermal variations and successful transmission even in demanding environments

Lossless 1×4 Silicon Photonic ROADM based on a Monolithic Integrated Erbium Doped Waveguide Amplifier on a Si3N4 platform

During the past years, incorporating ptical Circuit Switches (OCS) in high-bandwidth optical interconnects has outlined the critical challenges of achieving ultra-low fiber-to-fiber losses (FtF) and constantly decreasing costs for Photonic Integrated Circuits (PICs). This work aims to simultaneously satisfy both the low-loss and low-cost requirements by bringing two of the most successful example-technologies in the history of optics, i.e. EDFAs and ROADMs to a common Si<sub>3</sub>N<sub>4</sub> platform. In particular, the proof-of-concept operation of a lossless four-port Silicon Photonic (SiPho) ROADM is experimentally presented for the first time based on two PIC prototypes on a Si<sub>3</sub>N<sub>4</sub> platform, including a monolithic-integrated 5.9cm-long spiral Al<sub>2</sub>O<sub>3</sub>:Er<sup>3+</sup> Erbium Doped Waveguide Amplifier (EDWA) with 15 dB signal enhancement capabilities and a lattice MZI-interleaver ROAM layout with 100 GHz channel spacing. Considering an ultra-low 2.55 dB FtF loss of the ROADM along with 0.5 dB loss for each of the two coupling-interfaces between the Si<sub>3</sub>N<sub>4</sub> and Al<sub>2</sub>O<sub>3</sub>:Er<sup>3+</sup> waveguide layers, a cumulative loss of 3.55 dB is obtained, which can be compensated by the 3.6 dB net gain provided by the EDWA to four incoming WDM signals of -1.7 dBm/channel. Lossless wavelength-routing operation is validated at up to 240 Gb/s WDM (460Gb/s) data traffic, while the cascadability of the proposed device is benchmarked in a realistic two-stage optical bus topology with 10 km single mode fiber that selectively routes 425Gb/s WDM data channels to any of its eight Drop output ports. This work forms the first demonstration of lossless ROADM operation exclusively on SiPho technology, highlighting a promising roadmap for large scale SiPho switching matrices and more complex PICs co-integrated with EDWAs