Chalcogenide glass-based three-dimensional photonic crystals

Abstract

AsSeTe chalcogenide glasses are materials that are photosensitive and have a large refractive index. These properties make these glasses particularly suitable for the fabrication of photonic crystals. We present a way to build three-dimensional photonic structures from chalcogenide glasses using vapor deposition and direct holographic writing. We show that this technique is intrinsically self-aligned, providing a simple way to build layer-by-layer photonic crystals and a four-layer structure demonstrating the principle of the technique.

Interference lithography for 3D photonic band gap crystal layer by layer fabrication.

“…Chalcogenide glasses are highly promising materials for photonic crystals 3 . Their refractive index varies from 2.5 to 3, together with transparency from 800nm to 12 micron.…”

Direct Laser Writing of Three‐ Dimensional Photonic Crystals with a Complete Photonic Bandgap in Chalcogenide Glasses

“…This allows for selective chemical etching, making them suitable candidates for lithographic techniques. Therefore, chalcogenide glasses have already been used for the fabrication of 3D PCs, but previous work has been limited to opal infiltration [22][23][24] or LbL techniques, [5,6] where two-or three-beam holographic COMMUNICATIONS …”

“…[19] Each layer has to be fabricated with a whole set of lithography and etching steps. [3][4][5][6] Furthermore, ultra-precise alignment and wafer fusion for each additional layer is required at the cost of fabrication speed. Therefore, a technique combining both direct fabrication into a high-index material with the high flexibility, speed, and accuracy of direct laser writing is highly desirable.…”

“…However, the fabrication of highquality 3D structures for the optical regime still remains a challenge. Three techniques have been discussed: i) direct semiconductor fabrication by using a layer-by-layer (LbL) method, combining high-precision alignment and wafer-fusion techniques; [3][4][5][6] ii) templating by means of self-assembly of low-refractive-index colloidal microspheres; [7,8] and iii) holographic laser lithography [9,10] and direct laser writing (DLW) [11,12] to fabricate large-area, defect-free polymer templates. The latter two approaches require subsequent inversion [13][14][15] or double inversion [16,17] steps with high-refractiveindex materials.…”

“…Consecutive layers had to be stacked on top of each other and PCs with a maximum of four layers have been reported. [5,6] Here we use direct laser writing in 11 lm thick As 2 S 3 films by means of two-photon absorption. Thin chalcogenide films are fabricated through thermal evaporation of glassy As 2 S 3 at temperatures below 390°C and at low rates (see Experimental).…”