It's somehow similar to a random generator where you have 5 dices, roll them and then add to the entropy pool only if the total was even or odd. Changing the power is like forcing the system to use only 4 dices. It changes the probabilities a little, but not in a very controlable way, and with a good mixing in the entropy pool it's almost irrelevant.
Note if you look at the paper, you notice a close but not entirely perfect normal distribution, but nothing you cannot fix with UDNs and Irwin-Hall. For reference how that is done you can read the bottom of this very useful RNG article: https://people.ece.cornell.edu/land/courses/ece4760/RP2040/C...
My overall verdict on the tech in OP is that it is amazingly promising!
The specific mechanism is mentioned in the article:
https://en.wikipedia.org/wiki/Spontaneous_emission
> Although there is only one electronic transition from the excited state to ground state, there are many ways in which the electromagnetic field may go from the ground state to a one-photon state. That is, the electromagnetic field has infinitely more degrees of freedom, corresponding to the different directions in which the photon can be emitted. Equivalently, one might say that the phase space offered by the electromagnetic field is infinitely larger than that offered by the atom. This infinite degree of freedom for the emission of the photon results in the apparent irreversible decay, i.e., spontaneous emission.
Quantum noise is not based in any kind of physical information in the same way. It is intrinsically random. The "randomness" isn't merely a side effect of a bunch of physical phenomena. You cannot compromise a QRNG even if you had perfect knowledge of the state of every particle in the system over time.
https://www.jpmorgan.com/technology/technology-blog/certifie...
This sounds like more of a limitation of the model you are using than a limitation of reality.
Since you are always lacking that necessary physical information, it is always unpredictable. If it were otherwise, we would already know whether hidden variable theories of quantum mechanics (which lack intrinsic randomness) are correct or incorrect. But we don't know that. So intrinsic randomness doesn't make a difference to us. So quantum noise is useless.
It is possible for an electron to spontaneously gather enough voltage to break through a PN junction backwards. This shows up as a very noisy current measured in microamps.
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A forward bias PN junction might not be quantomly random. I'll have to research more. But a reverse bias PN junction is almost certainly quantum in nature.
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IMO, this is all just PN junction noise. Maybe LEDs are better than Zener diodes for noise. I'm pretty sure that noise characteristics are a guess and check methodology, it's all PN junctions of slightly different shapes after all.
A PN junction gives you only megabits/s of randomness at most.
This proposed method, if the article is correct, reaches gigabits/s.
But it could be because they are just using a large array.
In any case, a PRNG might be a no-go for many applications, out of principle.
And also, maybe a PRNG requires more power and die area than this new method?
So, there is nothing revolutionary going on there, this paper is more about how to build a system with micro-LEDs and a photodetector and how to remove any inherent biases in that system, with the obvious benefit of being able to make something very compact.
Still a bit unfortunate of a name clash since they're pretty much the opposite thing.
I guess the better term is just low-discrepancy sequence, which is also what Wikipedia uses.
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