2026/05/12 by J. Valenta, Michael Greben, Toranosuke Takagi +1 · 1 voice
Engineering · Physics and Astronomy · #Optical properties and cooling technologies in crystalline materials #Perovskite Materials and Applications #Strong Light-Matter Interactions
paper · pdf · doi:10.1021/acsnano.6c02074
openalex publication_date 2026/05/12 · openalex created_date 2026/05/13 · openalex updated_date 2026/07/13
High Resolution Image Download MS PowerPoint Slide Photoluminescence (PL) power efficiency, represented by the ratio of emitted to absorbed light energy, is a crucial factor for applications like radiative cooling. Yet, unlike PL quantum yield, achieving near-100% power efficiency in PL emitters remains mostly elusive. Here, we use spectrally resolved absolute radiometry method to study the PL quantum yield and power efficiency of solution-dispersed CsPbBr 3 quantum dots (QDs). The samples were optimized by ligand engineering and controlled aging over the span of several months. Absorption edge changes reveal that the aging causes self-healing of intraband defect states that are otherwise contributing to a decrease of the PL quantum yield. In the optimized samples, we observed PL quantum yield reaching 100% and the PL power efficiency also approaching unity. This result means that all the absorbed excitation light energy is reemitted as luminescence. For the excitation wavelength of 532 nm, the emitted light energy comprises ∼ 80% of anti-Stokes PL and 20% of Stokes-shifted PL, while for the wavelength of 543 nm, the emission is composed entirely of anti-Stokes PL. These parameters are promising for many potential advanced applications, such as radiative cooling.