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Photoelectric detectors cover a wide frequency spectrum spanning from the far ultraviolet to the infrared light with high sensitivity, large quantum efficiency and low dark current. The equivalent photoelectric detection of microwave frequency photons has remained elusive due to inherent differences between microwave photon energy and the interband transition energies exploited in standard photoelectric detectors. Here we present the realization of a near-ideal microwave photon to electron converter at a frequency typical of circuit quantum electrodynamics. These unique properties are enabled by the use of a high kinetic inductance disordered superconductor, granular aluminium, to enhance the light-matter interaction. This experiment constitutes an important proof of concept regarding low energy microwave photon to electron conversion unveiling new possibilities such as the detection of single microwave photons using charge detection. It finds significance in quantum research openning doors to a wide array of applications, from quantum-enhanced sensing to exploring the fundamental properties of quantum states., Comment: 10 pages, 8 figures. Include supplementary informations

Arranged patterns obtained by ultrafast laser processing on the surface of Ti/Cu/Ti/Si and Ti/Zr/Ti/Si thin film systems are reported. Two differently designed multilayer thin films, Ti/Cu/Ti/Si and Ti/Zr/Ti/Si, were deposited on silicon by the ion sputtering method. The bioactive surfaces on these systems involve the formation of laser-induced periodic surface structures (LIPSS) in each of the laser-written lines of mesh patterns on 5x5 mm areas. The formation of nano- and micro-patterns with an ultra-thin oxide film on the surfaces was used to observe the effects of morphology and proliferation of the MRC-5 cell culture line. To determine whether Ti-based thin films have a toxic effect on living cells, an MTT assay was performed. The relative cytotoxic effect as a percentage of surviving cells showed that there was no difference in cell number between the Ti-based thin films and the control cells. There was also no difference in the viability of the MRC-5 cells, except for the Ti/Cu/Ti/Si system, where there was a slight 10% decrease in cell viability., Comment: 15 pages, 6 figures

The need to repeatedly shuttle around synaptic weight values from memory to processing units has been a key source of energy inefficiency associated with hardware implementation of artificial neural networks. Analog in-memory computing (AIMC) with spatially instantiated synaptic weights holds high promise to overcome this challenge, by performing matrix-vector multiplications (MVMs) directly within the network weights stored on a chip to execute an inference workload. However, to achieve end-to-end improvements in latency and energy consumption, AIMC must be combined with on-chip digital operations and communication to move towards configurations in which a full inference workload is realized entirely on-chip. Moreover, it is highly desirable to achieve high MVM and inference accuracy without application-wise re-tuning of the chip. Here, we present a multi-core AIMC chip designed and fabricated in 14-nm complementary metal-oxide-semiconductor (CMOS) technology with backend-integrated phase-change memory (PCM). The fully-integrated chip features 64 256x256 AIMC cores interconnected via an on-chip communication network. It also implements the digital activation functions and processing involved in ResNet convolutional neural networks and long short-term memory (LSTM) networks. We demonstrate near software-equivalent inference accuracy with ResNet and LSTM networks while implementing all the computations associated with the weight layers and the activation functions on-chip. The chip can achieve a maximal throughput of 63.1 TOPS at an energy efficiency of 9.76 TOPS/W for 8-bit input/output matrix-vector multiplications.

The discovery that a gate electrode suppresses the supercurrent in purely metallic systems is missing a complete physical understanding of the mechanisms at play. We here study the origin of this reduction in a Superconductor-Normal metal-Superconductor Josephson junction by performing, on the same device, a detailed investigation of the gate-dependent switching probability together with the local tunnelling spectroscopy of the normal metal. We demonstrate that high energy electrons leaking from the gate trigger the reduction of the critical current which is accompanied by an important broadening of the switching histograms. The switching rates are well described by an activation formula including an additional term accounting for the injection of rare high energy electrons from the gate. The rate of electrons obtained from the fit remarkably coincides with the independently measured leakage current. Concomitantly, a negligible elevation of the local temperature is found by tunnelling spectroscopy which excludes overheating scenarios., Comment: 12 pages, 8 figures, include supplementary materials in appendix

We present early experiences with defining and validating a software maturity model (SMM) for a distributed, research-driven organization of independent and self-organizing teams of diverse cultures, experience and maturity. The paper briefly outlines the model, but focuses on the early stages of building and validating it. Based on that, we identify major factors contributing to the successful deployment of a SMM., Comment: 12 pages; preprint of EuroSPI 2019 paper

G\'EANT project is an example of a large organization with around 30 software projects and around 20 software development teams. Software development teams consist of many skilled associates coming from all members National Research and Education Networks. Three main issues that are common for all these software development teams and their members are: geographical distribution, scattered manpower percentage, and parallel involvement in other high priority projects in their native organizations. This paper presents a novel software maturity model that is designed specifically for G\'EANT software development teams and aims to address the described issues., Comment: 4 pages, 1 figure. Submitted to TELFOR 2018 conference