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

DEAERATOR

FIELD: sewage-purifying facilities.SUBSTANCE: the invention is pertaining to the field of sewage-purifying facilities, in particular, to facilities of a thermal deaeration of sewage. The deaerator of sewage contains a cylindrical body with a central funnel for the flashing steam withdrawal and a sewage delivering unit mounted tangentially to the body. The latter consists of two sections, the first of which represents a uniform chamber containing a steam feeding zone made in the form of a steam nozzle and a mixing zone made in the form of a convergent pipe chamber with the connecting pipes to feed in the deaerated sewage. And the second one represents a pressure chamber made with a convergent pipe section, a cylindrical section and a diffuser section. The technical result of the offered invention is a decrease of dimensions and metal consumption, as well as and as removal from a cycle of additional heat exchange devices for warming sewage up to the saturation temperature (96°-102°C).EFFECT: the invention ensures decreased dimensions and metal consumption, removal from the operation cycle of additional heat exchange devices for warming sewage up to the saturation temperature.3 dwg.Изобретение относится к водоочистным сооружениям, а именно к установкам термической деаэрации воды. Деаэратор воды содержит цилиндрический корпус с центральной трубой отвода выпара и водоподводящим блоком, установленным тангенциально корпусу, последний выполнен состоящим из двух секций, первая из которых представляет собой единую камеру, содержащую зону подвода пара, в виде парового сопла, и зону смешения в виде конфузорной камеры, с патрубками подвода деаэрируемой воды, а вторая - напорную камеру, выполненную с конфузорным, цилиндрическим и диффузорным участками. Техническим результатом заявленного изобретения является уменьшение габаритов и металлоемкости, а также удаление из цикла дополнительных теплообменных устройств для подогрева воды до температуры насыщения (96-102°С). 3 ил

Conversion of the Defense Industry and Ikansformation of the Economy of the USSR

The current development of the Soviet economy depends in large measure on the degree to which production and mobilizational military-production potential will be used to realize national-economic tasks.