Interaction of light with thin liquid membranes

Shaping the branched flow of light through disordered media

“…Demanding high transmission into a desired region by choosing high-transmission eigenchannels is thus clearly not enough to guarantee clean branch separation, since high transmission can also be obtained by propagating along multiple branches at once. In a possible optical experiment, such a mixing can be expected to be even more prevalent than in our numerical example, simply because optical implementations can typically involve a large number of branches (19).…”

“…Implementing such concepts in optics requires only a small sub-part of the transmission matrix and is thus within reach of present-day technology. We thank Miguel A. Bandres for fruitful discussions on his recent experiments [16]. We acknowledge support by the European Commission under project NHQWAVE (MSCA-RISE 691209).…”

“…In other words, for the experiments where branched flow was observed so far, the incoming wavefront as well as the potential that the wave explores were considered as predetermined and immutable. These limitations are currently about to be overcome in a new generation of experiments, where coherent laser light was observed to exhibit branching when propagating through very thin disordered materials, such as the surface layer of a soap bubble (19). Specifically, we expect that the transfer of branched flow to the optical domain will open up the whole arsenal of photonics to shape the wavefront of such branched light beams (20, 21).…”

“…We thank Miguel A. Bandres for fruitful discussions on his recent experiments (19) and Florian Libisch for his help with the numerical code. We acknowledge support by European Commission Project Non-Hermitian Quantum Wave Engineering (NHQWAVE, MSCA-RISE 691209) and by the Austrian Science Fund (FWF) through the Project SFB-NextLite F49-P10.…”