Exposure enhanced photoluminescence of CdS0.9Se0.1 quantum dots embedded in spin-coated Ge25S75 thin films

Abstract

Semiconductor quantum dots (QDs) are well known photoluminescent materials. Their potential practical applications depend on their physico-chemical and luminescent properties and also on the properties of hosting material. To ensure that QDs retain their photoluminescence during the preparation of a suitable solid composite form, the solution based casting techniques with deposition at lower temperatures are usually used. In our work, we have doped an inorganic Ge₂₅S₇₅ chalcogenide glass matrix with synthesized CdS_0.9Se_0.1 QDs and prepared thin films by the solution based spin-coating technique. In comparison with commonly used polymers the Ge₂₅S₇₅ chalcogenide glass thin films a possess high refractive index and wide VIS-NIR-MIR optical transparent region. We also report on the phenomenon of significant UV exposure induced increase of doped thin film photoluminescence intensity which can be exploited in local photo-induced photoluminescence enhancement of doped chalcogenide glass thin films.