Jingwen Yao,Yuling Huang,Haifeng Sun,Zhiyu Wang,Jie Xue,Zhifeng Huang,Shou-Cheng Dong,Xihan Chen,Haipeng Lu
Spin light-emitting diodes (spin-LEDs) are important for spin-based electronic circuits as they convert the carrier spin information to optical polarization. Recently, chiral-induced spin selectivity (CISS) has emerged as a new paradigm to enable spin-LED as it does not require any magnetic components and operates at room temperature. However, CISS-enabled spin-LED with tunable wavelengths ranging from red to near-infrared (NIR) has yet to be demonstrated. Here, chiral quasi-2D perovskites are developed to fabricate efficient spin-LEDs with tunable wavelengths from red to NIR region by tuning the halide composition. The optimized chiral perovskite films exhibit efficient circularly polarized luminescence from 675 to 788 nm, with a photoluminescence quantum yield (PLQY) exceeding 86% and a dissymmetry factor ( g lum ) ranging from 8.5 × 10 −3 to 2.6 × 10 −2 . More importantly, direct circularly polarized electroluminescence (CPEL) is achieved at room temperature in spin-LEDs. This work demonstrated efficient red and NIR spin-LEDs with the highest external quantum efficiency (EQE) reaching 12.4% and the electroluminescence (EL) dissymmetry factors ( g EL ) ranging from 3.7 × 10 −3 to 1.48 × 10 −2 at room temperature. The composition-dependent CPEL performance is further attributed to the prolonged spin lifetime as revealed by ultrafast transient absorption spectroscopy.
Qingqian Wang,Hongmei Zhu,Yangzhi Tan,Junjie Hao,Taikang Ye,Haodong Tang,Zhaojin Wang,Jingrui Ma,Jiayun Sun,Tianqi Zhang,Fankai Zheng,Wenda Zhang,Hoi Wai Choi,Wallace C. H. Choy,Dan Wu,Xiao Wei Sun,Kai Wang
Chiral-induced spin selectivity (CISS) effect provides innovative approach to spintronics and quantum-based devices for chiral materials. Different from the conventional ferromagnetic devices, the application of CISS effect is potential to operate under room temperature and zero applied magnetic field. Low dimensional chiral perovskites by introducing chiral amines are beginning to show significant CISS effect for spin injection, but research on chiral perovskites is still in its infancy, especially on spin-light emitting diode (spin-LED) construction. Here, the spin-QLEDs enabled by 2D chiral perovskites as CISS layer for spin-dependent carrier injection and CdSe/ZnS quantum dots (QDs) as light emitting layer are reported. The regulation pattern of the chirality and thickness of chiral perovskites, which affects the circularly polarized electroluminescence (CP-EL) emission of spin-QLED, is discovered. Notably, the spin injection polarization of 2D chiral perovskites is higher than 80% and the CP-EL asymmetric factor ( g CP-EL ) achieves up to 1.6 × 10 −2 . Consequently, this work opens up a new and effective approach for high-performance spin-LEDs.
危险品化学品经营许可证（带存储）