A New High-Performance Camera That Detects Single Photons

There may soon be breakthroughs in the search for dark matter. A new publication in Optics Express reveals a camera consisting of superconducting nanowires capable of detecting single photons, a useful feature for detecting light at the furthest ends of the infrared band. The high-performance camera, developed by the National Institute of Standards and Technology (NIST), boasts some of the best performing photon counters in the world in terms of speed, efficiency, and color detection. The detectors also have some of the lowest dark count rates of any photon sensor, resisting false signals from noise.

The size of the detectors comes out to 1.6mm on each side, packed with 1024 sensors for high resolution imagery and fabricated from silicon wafers cut into chips. The nanowires are made from tungsten and silicon alloy with leads made from superconducting niobium.

In order to prevent the sensors from overheating, a readout architecture was used based on a previous demonstration on a smaller camera with 64 sensors adding data from rows and columns. The research has been in collaboration with the National Aeronautics and Space Administration (NASA), which seeks to include the camera in the Origins Space Telescope project.

The eventual goal is to use the arrays to analyze chemical compositions of planets outside of our solar system. By observing the absorption spectra of light passing through an exoplanet’s atmosphere, information can be gathered on the elements in the atmosphere. Currently, large-area single-photon counting detector arrays don’t exist for measuring the mid- to far-infrared signatures, the spectrum range for elements that may indicate signs of life. While fabrication success is high, the efficiency of the detectors remains quite low, although there are plans to extend the current project into an even bigger camera with millions of sensors.

In addition to searching for chemical life on other planets, future  applications may include recording measurements to confirm the existence of dark matter.

[Thanks Qes for the tip!]

15 thoughts on “A New High-Performance Camera That Detects Single Photons

  1. To be clear, the fact that it can detect single photons isn’t exactly groundbreaking. Your eyes can detect single photons – and the quantum efficiency (how *often* it detects a single photon) isn’t really anything to write home about either, with a total efficiency (including the fill factor of each pixel) of ~8%. Avalanche photodiode arrays do better than that. The big advantage is the low dark count rate of below 1 kHz/pixel.

    1. I think the big advantage is its ability to measure mid to far infrared: “Currently, large-area single-photon counting detector arrays don’t exist for measuring the mid- to far-infrared signatures, the spectrum range for elements that may indicate signs of life.”

    2. Could you provide a reference for human eyes working as single photon detectors? I would have bet very good money on a single photon being far, far below the noise floor of mushy, biological eyes and nerves.

        1. Unless I’m missing something (and I could well be) that link says that the eye does not respond to single photons. It says that the retina ‘may’ respond to single photons but that isn’t sufficient. Firstly, the retina is only one part of the eye and secondly, ‘may respond’ is too weak a statement to then claim that the ‘eye can detect single photons’. To reliably detect them firstly you have to be sure that it *will* trigger and that secondly it *will not* randomly trigger because of the effects of your pulse, breathing, coffee, etc, etc, etc. Otherwise how would you know that your output was caused by a photon and not something else?
          So I remain unconvinced and will hang onto some ‘very good money’ for now!
          Interesting though, thanks for sharing the link

    1. “I’m totally shocked that publicly funded research is not behind a private companies pay wall!”
      If it’s not behind a paywall, the Chinese now own what we paid for – for free. And rest assured anything they to improve it will be kept very very secret.

  2. Why is a tungsten silicon alloy nanowire used for the sensor ?

    What I mean is that Tungsten has an atomic number of 74, would a heavier element have the potential to detect more spectral lines. Initially I thought that a heavier monoisotopic element like Gold-197, with an atomic number of 79, would be better but now I think more stable isotopes would be better.

    Is using 7 isotopes of tungsten an advantage ? Are they using all 7 isotopes or only the 4 stable isotopes to gain additional spectra absorption lines.

    And if heavier more stable isotopes are better, why isn’t Osmium (6 stable isotopes, atomic number 76) or a Mercury (7 stable isotopes, atomic number 80) alloy better. Is it because vacuum deposition with Tungsten is a well known process.

    I can see the advantage of having more potential spectral lines to better workaround Doppler shifts in astronomical observations.

  3. Digging through this I am trying to find the exact details on how this is special, it seems to be the bands at which this is effective but not 100% sure.

    I have a Photo-multiplier tube with a photon counter I bought on Ebay for about 200$, how is this considered better?

      1. The novel part is that it is a larger array (64×64 pixels, compared to the previous state of the art of 32×32) than has previously been demonstrated of superconducting single photon detectors.

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