Mid- to far-infrared sensing: SrTiO₃, a novel optical material

Polar dielectric crystals have been proposed as a disruptive technological solution to the inflated expectations of plasmonics. The excitation of low-loss surface-phonon polaritons and localized surface-phonon resonances throughout the IR spectrum gives rise to new opportunities, otherwise unachievable due to the inherent losses of metal-based plasmonics. In this work we present, for the first time, the exciting capabilities of SrTiO₃, an important technological material that has been overlooked as an active element for nano-photonics.