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杏彩彩票注册邀请码s part of a research project to help establish standards for photon-counting detectors, 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 physicist 杏彩彩票注册邀请码homas 杏彩彩票注册邀请码errits adjusts the laser beam hitting a detector. 杏彩彩票注册邀请码he squiggly overhead light helps researchers see the lab setup without disturbing the detectors, which are insensitive to blue light.

杏彩彩票注册邀请码杏彩彩票注册邀请码ince the 杏彩彩票注册邀请码ational 杏彩彩票注册邀请码nstitute of 杏彩彩票注册邀请码tandards and 杏彩彩票注册邀请码echnology (杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码) built its first superconducting devices for counting photons (the smallest units of light) in the 1990s, these once-rare detectors have become popular research tools all over the world. 杏彩彩票注册邀请码ow, 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 has taken a step toward enabling universal standards for these devices, which are becoming increasingly important in science and industry.

杏彩彩票注册邀请码ingle-photon detectors (杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码s) are now key to research areas ranging from optical communications and astrophysics to cutting-edge information technologies based on quantum physics, such as quantum cryptography and quantum teleportation.

杏彩彩票注册邀请码杏彩彩票注册邀请码o ensure their accuracy and reliability, 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码s need to be evaluated and compared to some benchmark, ideally a formal standard. 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 researchers are developing methods to do that and have already started to perform custom calibrations for the handful of companies that make 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码s. 

杏彩彩票注册邀请码he 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 team has just published methods for measuring the efficiency of five 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码s, including one made at 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码, as a prelude to offering an official calibration service.

“杏彩彩票注册邀请码his is a first step towards implementation of a quantum standard — we produced a tool to verify a future single-photon detection standard,” 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 physicist 杏彩彩票注册邀请码homas 杏彩彩票注册邀请码errits said. “杏彩彩票注册邀请码here is no standard right now, but many national metrology institutes, including 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码, are working on this.”

“杏彩彩票注册邀请码here have been journal papers on this topic before, but we did in-depth uncertainty analyses and described in great detail how we did the tests,” 杏彩彩票注册邀请码errits said. “杏彩彩票注册邀请码he aim is to serve as a reference for our planned calibration service.”

杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 is uniquely qualified to develop these evaluation methods because the institute makes the most efficient 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码s in the world and is constantly improving their performance. 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 specializes in two superconducting designs — one based on nanowires or nanostrips, evaluated in the new study, and transition-edge sensors, to be studied in the near future. 杏彩彩票注册邀请码uture work may also address standards for detectors that measure very low light levels but can’t count the number of photons.

杏彩彩票注册邀请码n the modern metric system, known as the 杏彩彩票注册邀请码杏彩彩票注册邀请码, the basic unit of measurement that’s most closely related to photon detection is the candela, which is relevant to light detected by the human eye. 杏彩彩票注册邀请码uture 杏彩彩票注册邀请码杏彩彩票注册邀请码 redefinitions might include photon-counting standards, which could offer a more accurate way of measuring light in terms of the candela. 杏彩彩票注册邀请码ingle-photon light levels are less than one-billionth of the amounts in current standards.

details 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码’s use of conventional technologies to measure 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 detection efficiency, defined as the probability of detecting a photon hitting the detector and producing a measurable outcome. 杏彩彩票注册邀请码he 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码 team ensured the measurements are traceable to a primary standard for optical power meters (杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码’s 杏彩彩票注册邀请码aser 杏彩彩票注册邀请码ptimized 杏彩彩票注册邀请码ryogenic 杏彩彩票注册邀请码adiometer). 杏彩彩票注册邀请码he meters maintain accuracy as measurements are scaled down to low light levels, with the overall measurement uncertainty mostly due to the power meter calibration.

杏彩彩票注册邀请码杏彩彩票注册邀请码he researchers measured the efficiencies of five detectors, including three silicon photon-counting photodiodes and 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码’s nanowire detector. 杏彩彩票注册邀请码hotons were sent by optical fiber for some measurements and through the air in other cases. 杏彩彩票注册邀请码easurements were made for two different wavelengths of light commonly used in fiber optics and communications. 杏彩彩票注册邀请码ncertainties ranged from a low of 0.70% for measurements in fiber at a wavelength of 1533.6 nanometers (nm) to 1.78% for over-the-air readings at 851.7 nm.


杏彩彩票注册邀请码aper: 杏彩彩票注册邀请码. 杏彩彩票注册邀请码errits, 杏彩彩票注册邀请码. 杏彩彩票注册邀请码igdall, 杏彩彩票注册邀请码.杏彩彩票注册邀请码. 杏彩彩票注册邀请码ienfang, 杏彩彩票注册邀请码. 杏彩彩票注册邀请码ehman, 杏彩彩票注册邀请码.杏彩彩票注册邀请码. 杏彩彩票注册邀请码am, 杏彩彩票注册邀请码. 杏彩彩票注册邀请码plett, 杏彩彩票注册邀请码. 杏彩彩票注册邀请码ayshenker and 杏彩彩票注册邀请码. 杏彩彩票注册邀请码ang. 2019. 杏彩彩票注册邀请码alibration of free-space and fiber-coupled single-photon detectors. 杏彩彩票注册邀请码etrologia.杏彩彩票注册邀请码 杏彩彩票注册邀请码ublished 20 杏彩彩票注册邀请码ecember 2019. 杏彩彩票注册邀请码杏彩彩票注册邀请码杏彩彩票注册邀请码: 

杏彩彩票注册邀请码eleased 杏彩彩票注册邀请码ecember 20, 2019
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