In this study, we introduce a modified microscope unit for studying fluorescence emitters under high-vacuum and ambient gas conditions. The modified microscope unit has an immersion objective and uses an ionic liquid as a refractive index matching medium. In our optical geometry, the immersion objective and ionic liquid are placed in high vacuum and ambient gas. The optical properties of single colloidal quantum dots (CdSe/ZnS) in a poly(methyl methacrylate) (PMMA) matrix placed in ambient air, high vacuum, and ambient nitrogen gas with an appropriate pressure are studied.

doi:10.1143/JJAP.49.01AE04