back to article Boffins sling around entangled photons at telco wavelengths

One of the hurdles facing photon-based quantum systems using entangled photons is that it's hard to create them at the 1550 nm wavelengths used in telecommunications systems. Entanglements are the basis for all sorts of hot-boffin stuff: quantum information processing, repeaters, photon-based key exchange, and fully quantum …

  1. frank ly

    re. hot-boffin stuff

    I was hoping for a picture of a hot boffin, for educational purposes.

    1. I3N

      Re: re. hot-boffin stuff

      And silly me, I'm picturing WR187 ....

      1. DropBear

        Re: re. hot-boffin stuff that some rectangular waveguide fetish thing...? Google seems to think so. Hey, I'm not judging...!

        1. I3N

          Re: re. hot-boffin stuff

          Well I do get the neurons worked up about soldering flanges on WR15, WR12, WR10 in a nitrogen rich atmosphere. Proper fixturing and all that >50dB S11.

          Of course that would be V-, E-, & W-Band in some nomenclatures.

          Too little beer lately ...

    2. phuzz Silver badge

      Re: re. hot-boffin stuff

      "I was hoping for a picture of a hot boffin"

      Your wish is my command:


      A boffin in the desert is clearly going to be hot.

  2. werdsmith Silver badge

    Sometimes when I'm alone and all is quiet, I sit and sob inconsolably because I chose computing and not physics.

    1. Anonymous Coward
      Anonymous Coward

      If its any consolation I studied degree level physics then chose computing, because advanced physics is really hard!

      1. druck Silver badge

        Me too, and all I can contribute is "whoosh".

        1. John Mangan

          Me too. At least we're not alone!

      2. Trigonoceps occipitalis

        Ernest Rutherford

        All science is either physics or stamp collecting.

    2. GX5000

      OMG you 2

      Three years then got hauled into PolSci, the Military then ran away into Technologist roles for the Gov.

      I want a redo in AstroPhys.

  3. Scroticus Canis

    So what is it good for?

    The entanglement will only last until the first repeater/router/switch decodes the photon to retransmit it. So just short range entanglement in real comms terms, not the end to end one desires, unless one can make a single fibre run connection.

    1. Kernel

      Re: So what is it good for?

      " So just short range entanglement in real comms terms"

      You do realise that 1550nm is the long-haul wavelength range used by telcos, don't you - so we're looking at distances in the order of 1000s of kms without having to decode or otherwise interfere with the photon. This sort of range is currently available off-the-shelf with existing DWDM systems, so no great break through required there.

      Hence the push to get it working at 1550nm - there's no commercial advantage to using this technology within a data centre or even across campus, but trans-Pacific or trans-Atlantic is a different story altogether. I doubt that the cryogenic requirement would be too much of an issue either - it used to be a requirement for the low noise amplifiers in satellite antennas, but it didn't stop that technology being widely deployed.

      If there's a significant economic advantage to this technology for long-haul carriers (and I suspect there is, capacity-wise) it will be developed into a stable and reliable commercial product surprisingly quickly.

  4. Jellied Eel Silver badge


    Distances are more like <100km for single mode fibre spans before amp/regen is needed. But the commercials will revolve around where the applications for tangled photons lie. Plus figuring out any SLAs.. Some work's been done already around quantum cryptography already, and capacity would rely on bits per qbit. Then cost to double capacity vs using another fibre or wavelength. Or it may lead to advances in quantum teleportation, and then no need for fibres at all.

    1. Anonymous Coward
      Anonymous Coward

      Re: Distance..

      If you have to decode it at a repeater in order to resend it on it's way, haven't you rather lost the point of using quantum encryption in the first place ?

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