Fabry–Perot Resonances in Rb <sub>3</sub> Sb <sub>2</sub> I <sub>9</sub> Microcrystals for Optical Sensing Applications
Rhombus-shaped thin Rb3Sb2I9 microcrystals are investigated for their photoluminescence (PL) spectral properties. The spectra show broad self-trapped excitonic emissions with superimposed periodic spectral modulations. Through numerical analysis and an appropriate interference function model, we demonstrate that these spectral modulations arise from Fabry–Perot (FP) interferences, which are rarely observed in halide perovskites. The microcrystal with thin, large flat facets acts as an FP resonating cavity with two parallel mirror surfaces that capture and resonate the incident light throughout the crystal. The FP resonances have been confirmed through 3D full-field finite difference time domain simulations, which reveal variations in electric field eigenmodes with different crystal thicknesses and incident wavelengths. These self-resonating highly sensitive FP microcrystals have potential applications in various lead-free optoelectronic devices, including optical sensors, and as absorption enhancers in perovskite solar cells.
Authors
- B. R. K. Nanda (ORCID: https://orcid.org/0000-0001-8330-4824)
- C. Sudakar (ORCID: https://orcid.org/0000-0003-2863-338X)
- Ayusmin Panda (ORCID: https://orcid.org/0009-0007-7681-6793)
- Rakshitha H. Ashwath
Institutions
- Indian Institute of Technology Madras (IN)
- Chianti Multifunctional Observatory (IT)
- Materials Design (France) (FR)
- Computational Physics (United States) (US)
Publication Details
- Journal
- ACS Applied Optical Materials
- Published
- 2025-01-09
- DOI
- https://doi.org/10.1021/acsaom.4c00438
- Primary Topic
- Perovskite Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Department of Science and Technology, Ministry of Science and Technology, India
- Ministry of Education, India