An Active Inrush Current Limiter Based on SCR Phase Shift Control for EV Charging Systems

This article gives an overview of the main passive solutions and active techniques, based on AC switches to limit inrush currents in medium power AC-DC converters （up to 3.7 kW） for electric vehicle charging systems. In particular, a strategy, based on SCR （silicon controlled rectifier） phase, shift control in a mixed rectifier bridge with diodes and thyristors, is proposed. The challenge is to help designers optimize the triggering delay of SCRs to both limit the peak value of inrush current spikes and optimize the charge duration of the DC-link capacitor. A mathematical model （Mathcad engineering tool） has been defined to point out, the interest of a variable triggering delay to control SCRs to meet the expectations described previously. Experimental measurements using an industrial evaluation board of the AC-DC converter demonstrate the robustness of the method.

Parallelization of frequency domain quantum gates:manipulation and distribution of frequency-entangled photon pairs generated by a 21 GHz silicon microresonator

Harnessing the frequency dimension in integrated photonics offers key advantages in terms of scalability,noise resilience,parallelization,and compatibility with telecom multiplexing techniques.Integrated ring resonators have been used to generate frequency-entangled states through spontaneous four-wave mixing.However,state-of-the-art integrated resonators are limited by trade-offs among size,spectral separation,and efficient photon pair generation.We have developed silicon ring resonators with a footprint below 0.05 mm^(2)providing more than 70 frequency channels separated by 21 GHz.We exploit the narrow frequency separation to parallelize and independently control 34 single qubit-gates with a single set of three off-the-shelf electro-optic devices.We fully characterize 17 frequency-bin maximally entangled qubit pairs by performing quantum state tomography.We demonstrate for the first time,we believe,a fully connected five-user quantum network in the frequency domain.These results are a step towards a generation of quantum circuits implemented with scalable silicon photonics technology,for applications in quantum computing and secure communications.

25 Gbps low-voltage hetero-structured silicongermanium waveguide pin photodetectors for monolithic on-chip nanophotonic architectures

Near-infrared germanium(Ge) photodetectors monolithically integrated on top of silicon-on-insulator substrates are universally regarded as key enablers towards chip-scale nanophotonics, with applications ranging from sensing and health monitoring to object recognition and optical communications. In this work, we report on the highdata-rate performance pin waveguide photodetectors made of a lateral hetero-structured silicon-Ge-silicon(Si-Ge-Si) junction operating under low reverse bias at 1.55 μm. The pin photodetector integration scheme considerably eases device manufacturing and is fully compatible with complementary metal-oxide-semiconductor technology. In particular, the hetero-structured Si-Ge-Si photodetectors show efficiency-bandwidth products of^9 GHz at-1 V and ~30 GHz at-3 V, with a leakage dark current as low as ~150 nA, allowing superior signal detection of high-speed data traffic. A bit-error rate of 10-9 is achieved for conventional 10 Gbps, 20 Gbps, and25 Gbps data rates, yielding optical power sensitivities of-13.85 dBm,-12.70 dBm, and-11.25 dBm, respectively. This demonstration opens up new horizons towards cost-effective Ge pin waveguide photodetectors that combine fast device operation at low voltages with standard semiconductor fabrication processes, as desired for reliable on-chip architectures in next-generation nanophotonics integrated circuits.

Broadband supercontinuum generation in nitrogen-rich silicon nitride waveguides using a 300 mm industrial platform

We report supercontinuum generation in nitrogen-rich(N-rich)silicon nitride waveguides fabricated through back-end complementary-metal-oxide-semiconductor(CMOS)-compatible processes on a 300 mm platform.By pumping in the anomalous dispersion regime at a wavelength of 1200 nm,two-octave spanning spectra covering the visible and near-infrared ranges,including the O band,were obtained.Numerical calculations showed that the nonlinear index of N-rich silicon nitride is within the same order of magnitude as that of stoichiometric silicon nitride,despite the lower silicon content.N-rich silicon nitride then appears to be a promising candidate for nonlinear devices compatible with back-end CMOS processes.