Defect-Mediated Electronic Processes in Perovskites Revealed by Luminescence:From Fundamentals to Neuromorphic Computing
报告题目：Defect-Mediated Electronic Processes in Perovskites Revealed by Luminescence:From Fundamentals to Neuromorphic Computing
报 告 人：Ivan Scheblykin（教授）
报告日期：2025年11月19日 星期三
报告时间：下午14:40-15:40
报告地点：激光光谱研究所三层报告厅
报告简介：
Methods inspired by single-molecule spectroscopy, traditionally applied to molecules and quantum dots, have proven highly effective for investigating sub-micrometer metal-halide perovskite crystals and thin films. In these nano-structured systems, charge dynamics are often governed by only a few discrete carriers and defect states, leading to a so-called “digitized” regimes where conventional continuous semiconductor models no longer directly apply.1 Phenomena such as blinking photoluminescence expose metastable non-radiative centers, effects of ion migration and self-healing.2 We further demonstrate that crystal size beyond the quantum confinement effect plays an important role in determining the photoluminescence quantum yield (PLQY), underscoring the importance of spatial structure in the range 50 - 200 nm in luminescent materials.
Furthermore, we explore how charge trapping induces memory effects in the PL response, forming the basis for an optical memristor, or memlumor—a luminescent memory element with state-dependent PLQY.3 These perovskite-based memlumors leverage photodoping and photochemistry to encode volatile and non-volatile optical memory over timescales from nanoseconds to days. Using a novel multi-pulse time-resolved PL technique, we demonstrate ultralow switching energies (in the femtojoule range) and sub-microsecond classification of binary optical pulse patterns, positioning memlumors as promising components for neuromorphic optical computing.4
References:
(1) Adv. Energy Mater. 2020, 10 (46), 2001724.
(2) ACS Nano 2017, 11 (6), 5391–5404.
(3) ACS Energy Lett. 2024, 9 (5), 2075–2082.
(4) ACS Energy Lett. 2025, 10 (8), 3729–3734.
报告人简介：
Ivan Scheblykin received his Ph.D. in 1999 from the Moscow Institute of Physics and Technology and the Lebedev Physical Institute of the Russian Academy of Sciences, where he studied exciton dynamics in J-aggregates. After a postdoctoral fellowship at KU Leuven, Belgium, he moved to Sweden in 2002 to establish the Single Molecule Spectroscopy Group at Lund University’s Division of Chemical Physics, becoming a full professor in 2014. His research focuses on the fundamental photophysics of organic and inorganic semiconductors, with emphasis on energy transfer, charge migration, and trapping. A central theme of his work is uncovering physical and chemical processes that lie beyond ensemble averaging in optoelectronic materials, with current interests in charge dynamics in perovskite semiconductors. He is widely recognized for his expertise in photoluminescence spectroscopy, including time-resolved and single-molecule techniques.
