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Physicist Uses Laser Light As Fast, True-Random Number Generator

Posted by Soulskill on from the everything-is-better-with-lasers dept.

MrKevvy writes "An Ottawa physicist is using laser light to create truly random numbers much faster than other methods do, with obvious potential benefits to cryptography: 'Sussman's Ottawa lab uses a pulse of laser light that lasts a few trillionths of a second. His team shines it at a diamond. The light goes in and comes out again, but along the way, it changes. ... It is changed because it has interacted with quantum vacuum fluctuations, the microscopic flickering of the amount of energy in a point in space. ... What happens to the light is unknown — and unknowable. Sussman's lab can measure the pulses of laser light that emerge from this mysterious transformation, and the measurements are random in a way that nothing in our ordinary surroundings is. Those measurements are his random numbers.'"

3 of 326 comments (clear)

  1. Skip the newspaper article... by Vario · · Score: 5, Informative

    The newspaper article is not giving any information that is not already included in the summary.

    The paper is published in Optics Express, the abstract can be read here. The full article is behind a paywall unfortunately. The author claim that this concept could deliver random numbers at a rate of 100 GHz which is quite fast compared to other true random number generators out there that are based on thermal noise, radiation or other processes.

  2. Re:You should have said by Anonymous Coward · · Score: 5, Informative

    Sigh. You kids who can't remember 10 years ago.

  3. Re:Simtec "Entropy Key" also does quantum RNG by evanbd · · Score: 4, Informative

    You can also use resistor noise, a good amplifier, and an ADC to make moderately high bandwidth true quantum RNG. I priced out a simple design with a microcontroller on a USB key footprint; looked like $50-100 in prototype quantities, less in large quantities, for 10 KB/s output (or so). Getting the entropy is looked like the easy part; it then needed a fair bit of CPU power (by microcontroller standards) to hash that into usable bits.

    You can also (with a lot more software work, and low bitrates) use the resistor noise present in audio input channels to good effect. Turbid is a project that does just that. Note that when evaluating such projects, the hard part is not getting the numbers, but proving that they have enough entropy, and that they've been properly processed to preserve it. Turbid does an excellent job on this important documentation step.