Université de Fribourg

Experimental tuning of transport regimes in hyperuniform disordered photonic materials

Aubry, Geoffroy J. ; Froufe-Pérez, Luis S. ; Kuhl, Ulrich ; Legrand, Olivier ; Scheffold, Frank ; Mortessagne, Fabrice

In: Physical Review Letters, 2020, vol. 125, no. 12, p. 127402

We present wave transport experiments in hyperuniform disordered arrays of cylinders with high dielectric permittivity. Using microwaves, we show that the same material can display transparency, photon diffusion, Anderson localization, or a full band gap, depending on the frequency ν of the electromagnetic wave. Interestingly, we find a second weaker band gap, which appears to be related to...

Université de Fribourg

Magnetic-field effects on one-dimensional Anderson localization of light

Schertel, Lukas ; Irtenkauf, Oliver ; Aegerter, Christof M. ; Maret, Georg ; Aubry, Geoffroy J.

In: Physical Review A, 2019, vol. 100, no. 4, p. 043818

Transport of coherent waves in multiple-scattering media may exhibit fundamental, nonintuitive phenomena such as halt of diffusion by disorder called Anderson localization. For electromagnetic waves, this phenomenon was observed only in one and two dimensions so far. However, none of these experiments studied the contribution of reciprocal paths nor their manipulation by external fields. In...

Université de Fribourg

Topological effects of a vorticity filament on the coherent backscattering cone

Aubry, Geoffroy J. ; Roux, Philippe

In: Physical Review Letters, 2019, vol. 123, no. 3, p. 035503

In this Letter, we report on the effects of a vorticity filament on the coherent backscattering cone. Using ultrasonic waves in a strongly reverberating cavity, we experimentally show that the discrete number of loops of acoustic paths around a pointlike vortex located at the center of the cavity drives the cancellation and the potential rebirth of the coherent backscattering enhancement. The...

Université de Fribourg

The structural colors of photonic glasses

Schertel, Lukas ; Siedentop, Lukas ; Meijer, Janne-Mieke ; Keim, Peter ; Aegerter, Christof M. ; Aubry, Geoffroy J. ; Maret, Georg

In: Advanced Optical Materials, 2019, p. 1900442

The color of materials usually originates from a combination of wavelength‐dependent absorption and scattering. Controlling the color without the use of absorbing dyes is of practical interest, not only because of undesired bleaching properties of dyes but also regarding minimization of environmental and health issues. Color control without dyes can be achieved by tuning the material's...