Université de Fribourg

Photonic hyperuniform networks obtained by silicon double inversion of polymer templates

Muller, Nicolas ; Haberko, Jakub ; Marichy, Catherine ; Scheffold, Frank

In: Optica, 2017, vol. 4, no. 3, p. 361–366

Hyperuniform disordered networks belong to a peculiar class of structured materials predicted to display isotropic complete photonic bandgaps for a refractive index contrast larger than 3. The practical realization of such photonic designer materials is challenging, however, as it requires control over a multi-step fabrication process on optical length scales. Here we report the direct-laser...

Université de Fribourg

Role of short-range order and hyperuniformity in the formation of band gaps in disordered photonic materials

Froufe-Pérez, Luis S. ; Engel, Michael ; Damasceno, Pablo F. ; Muller, Nicolas ; Haberko, Jakub ; Glotzer, Sharon C. ; Scheffold, Frank

In: Physical Review Letters, 2016, vol. 117, no. 5, p. 053902

We study photonic band gap formation in two-dimensional high-refractive-index disordered materials where the dielectric structure is derived from packing disks in real and reciprocal space. Numerical calculations of the photonic density of states demonstrate the presence of a band gap for all polarizations in both cases. We find that the band gap width is controlled by the increase in...

Université de Fribourg

High-quality photonic crystals with a nearly complete band gap obtained by direct inversion of woodpile templates with titanium dioxide

Marichy, Catherine ; Muller, Nicolas ; Froufe-Pérez, Luis S. ; Scheffold, Frank

In: Scientific Reports, 2016, vol. 6, p. 21818

Photonic crystal materials are based on a periodic modulation of the dielectric constant on length scales comparable to the wavelength of light. These materials can exhibit photonic band gaps; frequency regions for which the propagation of electromagnetic radiation is forbidden due to the depletion of the density of states. In order to exhibit a full band gap, 3D PCs must present a threshold...

Université de Fribourg

Direct laser writing of three-dimensional network structures as templates for disordered photonic materials

Haberko, Jakub ; Muller, Nicolas ; Scheffold, Frank

In: Physical Review A, 2014, vol. 88, no. 4, p. 043822

In the present article we substantially expand on our recent study about the fabrication of mesoscale polymeric templates of disordered photonic network materials [Haberko and Scheffold, Opt. Expr. 21, 1057 (2013)]. We present a detailed analysis and discussion of important technical aspects related to the fabrication and characterization of these fascinating materials. Compared to our initial...

Université de Fribourg

Silicon hyperuniform disordered photonic materials with a pronounced gap in the shortwave infrared

Muller, Nicolas ; Haberko, Jakub ; Marichy, Catherine ; Scheffold, Frank

In: Advanced Optical Materials, 2014, vol. 2, no. 2, p. 115-119

The mesoscale fabrication of silicon hyperuniform disordered materials with a broad and pronounced photonic gap in the shortwave infrared is reported. Due to their unique structure and their high refractive index, these fascinating materials are predicted to possess a complete photonic bandgap in the absence of any long-range order.

Université de Fribourg

Efficient generation of Bessel beam arrays by means of an SLM

Bowman, R. ; Muller, Nicolas ; Zambrana-Puyalto, X. ; Jedrkiewicz, O. ; Trapani, P. Di ; Padgett, M. J.

In: The European Physical Journal - Special Topics, 2011, vol. 199, no. 1, p. 159-166

We use a Spatial Light Modulator (SLM) to produce arrays of Bessel beams by using multiple axicon phase-masks on the SLM. This approach utilises the whole of the SLM, rather than just a thin annular region (which is the case if the SLM is in the far-field of the generated Bessel beams). Using the whole SLM rather than just an annular region means that the required intensity on the SLM is an order...