This video offers an overview of Alexis Kirke’s Cloud Chamber – a work for violin and subatomic particles.
The first two minutes of the video are a discussion of the technical aspects, which is followed by a preview of the effect created by the cloud chamber processing.
via alexisk001:
The synthesizer settings are fixed for this demo, but can be varied so that the particles make non-pitched noises, violin bows, high beeps and more complex swoops.
(Demo of the system used by composer Alexis Kirke to create a performance for violin and subatomic particles.)
So what they have is a source of true randomness and some gear to (crudely) digitize it.
Never been a fan of using randomness (true or pseudo) for controlling pitch directly.
It can be useful to produce variations in sounds, but usually it's more fun to introduce any randomness at a few steps remove, eg to select a rule or phrase from a predefined table or similar.
And you don't really need those gadgets either – there are fast algorithms that can produce noise that doesn't repeat or show recognizable patterns in billions of years (at samplerate).