Research Team Led by Jang Joon-ik, Professor in the Department of Physics, Observes Two-Photon Resonant Raman Scattering in Perovskites for the First Time
The research findings of a team led by Professor Jang Joon-ik in the Department of Physics (First authors: Combined M.S./Ph.D. student Shin Seung-han and Master’s student Nam Seo-hyun) were published on March 25 in Advanced Functional Materials, a prestigious international journal in applied physics (2025 JCR Impact Factor: 19.0, Top 4.8%). This study was conducted in collaboration with a research team from Yonsei University and was supported by the National Research Foundation of Korea (Basic Research Laboratory Program and Individual Basic Research Program).
Smartphones, cameras, LED lighting, and solar cells: at the core of all these technologies lies the interaction between light and matter. Professor Jang Joon-ik’s research team has succeeded in observing the "two-photon resonant Raman scattering (TRRS)" phenomenon for the first time in two-dimensional halide perovskite (PEA)₂PbI₄, a material garnering significant attention as a next-generation semiconductor.
In simple terms, this phenomenon occurs when two photons (the particles of light) enter a semiconductor simultaneously, pass through an energy state called a “biexciton,” and are then emitted as light with a different color from the original. This quantum-mechanical phenomenon can be likened to two people jumping on a trampoline simultaneously, where the interaction propels one of them much higher. The research team systematically identified the conditions under which TRRS occurs, specifically the light intensity (threshold), temperature range, and polarization conditions.
Previously, TRRS had only been observed at cryogenic temperatures near that of liquid helium (around -269°C) in certain wide-bandgap semiconductors such as CuCl and CuBr. However, by leveraging the strong quantum and dielectric confinement effects of two-dimensional perovskites, the research team has succeeded for the first time in realizing this phenomenon at temperatures above -183°C (approximately 90 K)—the liquid nitrogen temperature range. This demonstrates that the material possesses exceptional nonlinear optical properties.
This study demonstrates that two-dimensional perovskites can serve as a platform for various nonlinear optical phenomena based on strong biexcitons. This discovery is expected to expand into areas such as biexciton-based nonlinear optical signal processing, precision exciton resonance spectroscopy, quantum optical communications, and optical device applications. Furthermore, switching to bromine- or chlorine-based perovskites is projected to enable TRRS at even higher temperatures due to stronger Coulomb coupling. By suggesting potential applications in other 2D materials, such as monolayer transition metal dichalcogenides, the team has established a significant milestone toward the ultimate development of room-temperature, biexciton-based quantum optical devices.
▶Title: Observation of Two-Photon Resonant Raman Scattering via the Biexciton Level in Two-Dimensional Halide Perovskite (C6H5C2H4NH3)2PbI4
▶Direct Link to the Paper: https://doi/10.1002/adfm.75110
[Keyword]
Quantum Optics, Semiconductor Physics, Next-Generation Materials
[Summary]
Through semiconductor physics research, Professor Jang Joon-ik's team has achieved the world's first observation of two-photon resonant Raman scattering (TRRS) in 2D perovskites. This breakthrough in quantum optics demonstrates the material's potential for next-generation materials, paving the way for high-temperature quantum devices and advanced optical signal processing.
Smartphones, cameras, LED lighting, and solar cells: at the core of all these technologies lies the interaction between light and matter. Professor Jang Joon-ik’s research team has succeeded in observing the "two-photon resonant Raman scattering (TRRS)" phenomenon for the first time in two-dimensional halide perovskite (PEA)₂PbI₄, a material garnering significant attention as a next-generation semiconductor.
In simple terms, this phenomenon occurs when two photons (the particles of light) enter a semiconductor simultaneously, pass through an energy state called a “biexciton,” and are then emitted as light with a different color from the original. This quantum-mechanical phenomenon can be likened to two people jumping on a trampoline simultaneously, where the interaction propels one of them much higher. The research team systematically identified the conditions under which TRRS occurs, specifically the light intensity (threshold), temperature range, and polarization conditions.
Previously, TRRS had only been observed at cryogenic temperatures near that of liquid helium (around -269°C) in certain wide-bandgap semiconductors such as CuCl and CuBr. However, by leveraging the strong quantum and dielectric confinement effects of two-dimensional perovskites, the research team has succeeded for the first time in realizing this phenomenon at temperatures above -183°C (approximately 90 K)—the liquid nitrogen temperature range. This demonstrates that the material possesses exceptional nonlinear optical properties.
This study demonstrates that two-dimensional perovskites can serve as a platform for various nonlinear optical phenomena based on strong biexcitons. This discovery is expected to expand into areas such as biexciton-based nonlinear optical signal processing, precision exciton resonance spectroscopy, quantum optical communications, and optical device applications. Furthermore, switching to bromine- or chlorine-based perovskites is projected to enable TRRS at even higher temperatures due to stronger Coulomb coupling. By suggesting potential applications in other 2D materials, such as monolayer transition metal dichalcogenides, the team has established a significant milestone toward the ultimate development of room-temperature, biexciton-based quantum optical devices.
▶Title: Observation of Two-Photon Resonant Raman Scattering via the Biexciton Level in Two-Dimensional Halide Perovskite (C6H5C2H4NH3)2PbI4
▶Direct Link to the Paper: https://doi/10.1002/adfm.75110
[Keyword]
Quantum Optics, Semiconductor Physics, Next-Generation Materials
[Summary]
Through semiconductor physics research, Professor Jang Joon-ik's team has achieved the world's first observation of two-photon resonant Raman scattering (TRRS) in 2D perovskites. This breakthrough in quantum optics demonstrates the material's potential for next-generation materials, paving the way for high-temperature quantum devices and advanced optical signal processing.