Interdisciplinary seminar | 17 October 2025

Controlling light emission dynamically is essential for the progress of integrated photonic technologies [1–3], but traditional systems struggle with issues related to size reduction, efficiency, and tunability. In this work, we present a hybrid platform combining Ge2Sb2Te5 (GST) [4] and perovskites [5] that enables versatile control of light emission within a compact structure.

We showcase four distinct functionalities: reversible switching of intensity and wavelength, activation of perovskite photoluminescence via third harmonic generation in GST, and wavefront manipulation through beam focusing. By exploiting the fast phase-change properties and high refractive index contrast of GST, our approach allows for dynamic, non-volatile tuning without the need for lithography, using selective phase patterning or maskless etching instead. This integration of GST's tunability with the light-emitting capabilities of perovskites addresses the limitations of conventional static metasurfaces and offers a scalable path toward ultracompact, reconfigurable light sources for applications in quantum optics, holography, and on-chip sensing.

This research was supported by Priority 2030 Federal Academic Leadership Program.

[1] H. Kim et al., Optical Metasurfaces for Biomedical Imaging and Sensing, ACS Nano, 19, 3085–3114, (2025).
[2] H. Altug et al., Advances and applications of nanophotonic biosensors, Nature Nanotechnology, 17, 5–16, (2022).
[3] Q. Li et al. Metasurface-enhanced biomedical spectroscopy, Nanophotonics 14, 1045–1068, (2025).
[4] S. Raoux and M. Wuttig, Phase Change Materials: Science and Applications (Springer), 1–18, (2009).
[5] Protesescu L. et al., Nanocrystals of cesium lead halide perovskites (CsPbX3, X= Cl, Br, and I): novel optoelectronic materials showing bright emission with wide color gamut, Nano Letters, 15, 3692–3696, (2015).