Paper accepted! 🥳

"Explaining and exploiting the radial memory effect in multimode optical fibres"

(A slightly older version is on ArXiv: https://arxiv.org/abs/2508.11389 )

When (coherent) light propagates in a multimode fibre, each mode accumulates a slightly different phase, so the output looks like a random speckle patter.
But it is NOT random!
This non-randomness has a number of consequences, among them the fact that the you get predictable patterns in the apparently random output. We show that a focused input will always result in a ring of excess intensity at the same radius of the input, we give a simple but rigorous explanation of why this happens, and suggest how this might be useful in practice.

#Optics #OpticalFibers #SpeckleCorrelations