Jiao Yujie, Li Zhenqin, Aihemaiti Nuerbiya, Ding Jiayu, Gu Bing, Peng Siying
Zhejiang University, Hangzhou, Zhejiang 310027, China.
School of Engineering, Westlake University, Hangzhou, Zhejiang 310030, China.
J Phys Chem Lett. 2024 Sep 5;15(35):9092-9099. doi: 10.1021/acs.jpclett.4c01878. Epub 2024 Aug 28.
Ultrafast spin manipulation for optical spin-logic applications requires material systems with strong spin-selective light-matter interactions. The optical Stark effect can realize spin-selective light-matter interactions by breaking the degeneracy of spin-selective transitions with an external electric field. Halide perovskites have large exciton binding energies, which enable a room-temperature optical Stark effect. However, halide perovskites are prone to degradation when interacting with light and polar solvents, limiting further integration with nanophotonic structures. We demonstrate a hybrid material system consisting of CsPbBr nanocrystal glass weakly coupled to resonant plasmonic silver nanoparticles, showing ultrafast tunable spin-based polarization selectivity at room temperature. We performed circularly polarized pump-probe characterizations to investigate the optical Stark effect in this material system, which resulted in a maximum energy shift of ∼3.67 meV (detuning energy of 0.11 eV and pump intensity of 0.62 GW/cm). We show that halide perovskite nanocrystal glasses have excellent resistance to heat and moisture, which may be favorable for integration with nanophotonic structures for further engineering polarization states, energy tuning, and coherence time.
用于光学自旋逻辑应用的超快自旋操控需要具有强自旋选择性光与物质相互作用的材料系统。光学斯塔克效应可以通过外部电场打破自旋选择性跃迁的简并性来实现自旋选择性光与物质的相互作用。卤化物钙钛矿具有较大的激子结合能，这使得室温下的光学斯塔克效应成为可能。然而，卤化物钙钛矿在与光和极性溶剂相互作用时容易降解，限制了其与纳米光子结构的进一步集成。我们展示了一种由弱耦合到共振等离子体银纳米颗粒的CsPbBr纳米晶玻璃组成的混合材料系统，在室温下表现出超快可调谐的基于自旋的偏振选择性。我们进行了圆偏振泵浦 - 探测表征，以研究该材料系统中的光学斯塔克效应，其导致最大能量偏移约为3.67毫电子伏特（失谐能量为0.11电子伏特，泵浦强度为0.62吉瓦/平方厘米）。我们表明卤化物钙钛矿纳米晶玻璃具有优异的耐热性和防潮性，这可能有利于与纳米光子结构集成，以进一步设计偏振态、能量调谐和相干时间。
