Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths

Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present SNSPDs embedded in nanophotonic integrated circuits which achieve internal quantum efficiencies close to unity at 1550 nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noise-equivalent powers in the 10-19 W/Hz-1/2 range and the timing jitter is as low as 35 ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms

Development of personnel of enterprises in system of intrafirm training

В статье рассматриваются проблемы формирования содержания подготовки рабочих в системе внутрифирменного обучения. Предлагается компетентностный подход для отбора, структурирования и формирования содержания внутрифирменного обученияThe article considers problems of formation of the content of training of workers to in-house training. Offers a competence-based approach for the selection, structuring and forming the content of in-house trainin

Corporate educational space of the modern enterprise: a phenomenological approach

В статье описываются уровни организации функционирования корпоративного образовательного пространства: глобальный, локальный, общий и частный. Корпоративное образовательное пространство рассматривается как система с позиций феноменологического подходаThe levels of organization of functioning of the corporate education space: global, local, shared, and private are describes the article. The corporate educational space is considered as a system from the standpoint of the phenomenological approac

Neuropsychological analysis of peculiarities of formation of graphomotor skills in primary school children

Functions of serial organization of movements and actions and their role in the formation and development of graphomotor skills (writing in particular) in primary school children (193 pupils of 1st and 3dgrades) were investigated using traditional neuropsychological and new computerized methods. It allowed to trace the processes of automatization of graphomotor skill in normally developed children and to describe specific difficulties of graphomotor activity in children with learning disabilities

On-chip coherent detection with quantum limited sensitivity

While single photon detectors provide superior intensity sensitivity, spectral resolution is usually lost after the detection event. Yet for applications in low signal infrared spectroscopy recovering information about the photon’s frequency contributions is essential. Here we use highly efficient waveguide integrated superconducting single-photon detectors for on-chip coherent detection. In a single nanophotonic device, we demonstrate both single-photon counting with up to 86% on-chip detection efficiency, as well as heterodyne coherent detection with spectral resolution f/∆f exceeding 1011. By mixing a local oscillator with the single photon signal field, we observe frequency modulation at the intermediate frequency with ultra-low local oscillator power in the femto-Watt range. By optimizing the nanowire geometry and the working parameters of the detection scheme, we reach quantum-limited sensitivity. Our approach enables to realize matrix integrated heterodyne nanophotonic devices in the C-band wavelength range, for classical and quantum optics applications where single-photon counting as well as high spectral resolution are required simultaneously

Superconducting parallel nanowire detector with photon number resolving functionality

We present a new photon number resolving detector (PNR), the Parallel Nanowire Detector (PND), which uses spatial multiplexing on a subwavelength scale to provide a single electrical output proportional to the photon number. The basic structure of the PND is the parallel connection of several NbN superconducting nanowires (100 nm-wide, few nm-thick), folded in a meander pattern. Electrical and optical equivalents of the device were developed in order to gain insight on its working principle. PNDs were fabricated on 3-4 nm thick NbN films grown on sapphire (substrate temperature TS=900C) or MgO (TS=400C) substrates by reactive magnetron sputtering in an Ar/N2 gas mixture. The device performance was characterized in terms of speed and sensitivity. The photoresponse shows a full width at half maximum (FWHM) as low as 660ps. PNDs showed counting performance at 80 MHz repetition rate. Building the histograms of the photoresponse peak, no multiplication noise buildup is observable and a one photon quantum efficiency can be estimated to be QE=3% (at 700 nm wavelength and 4.2 K temperature). The PND significantly outperforms existing PNR detectors in terms of simplicity, sensitivity, speed, and multiplication noise