The development of novel sensing systems requires breakthroughs in the conception of multifunctional materials. In this sense, while extensive research has been dedicated to the individual tuning of the electrical or optical properties of different materials, the combination of both features would result in a promising field of research that would further extend opportunities for engineering novel function in sensor geometries. In the present work, we employed a highly attractive optical material for mid-infrared (MIR) sensing (chalcogenide glasses, ChG) and focused on the spatial control of its surface electrical potential via a thermoelectrical imprinting process. Different glass compositions based on the system Ge-Sb-S-Na were prepared by varying the sulfur stoichiometry and the sodium content. Each glass was thermally poled using electrodes with specific patterns, and subsequent structural modifications and surface electrical potential were then evaluated via Raman spectroscopy and Kelvin Probe Force Microscopy (KPFM). Raman cartographies show structural modifications attributed to alkali depletion following the patterns of the electrodes used for the imprinting process. Furthermore, KPFM measurements show clearly defined motifs on the electrical potential which are associated to charges implanted into the glass matrix. It was shown that the surface potential can vary in sign within an amplitude range of 10V and exhibit patterning at the micrometer scale. We observed that the efficiency of the surface

Chalcogenide glasses exhibit a wide transparency domain spanning from near infrared (IR) to mid-IR and thus, have become highly attractive optical materials in a range of applications. Controlling the topology of these glasses can be seen as a key aspect for the design of optical elements such as gratings, metasurfaces, waveguides, and other diverse refractive and diffractive optical components. Here, we demonstrate the structuring of large, millimeter square areas that have been structured at the micrometer scale employing an easy two-step process, incorporating a micro-poling step followed by immersion in an amine solvent. Ge-Sb-S-Na glasses have been investigated, and the influence of the sulphur and sodium content on the pre- and post-poling material dissolution response has been discussed. Three compositions of varying sulphur and sodium content were selected to study the influence of thermal poling using either a homogeneous or a structured electrode. It was found that either a large difference in dissolution rates of poled and unmodified regions or a large poled layer thickness leads to the generation of significant topological contrast. The origin of the poled region’s selective etching has been explained on the basis of a poling-induced density decrease. Finally, it was demonstrated that when the targeted resolution is micrometric, this rather easy process could be employed as an alternative to classical lithography techniques.

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