Department of Chemistry, National University of Singapore, Singapore, 117543, Singapore.
SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for Optoelectronic Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, 518060, China.
Adv Mater. 2022 Jun;34(25):e2101895. doi: 10.1002/adma.202101895. Epub 2021 Jun 19.
Mimicking memory processes, including encoding, storing, and retrieving information, is critical for neuromorphic computing and artificial intelligence. Synaptic behavior simulations through electronic, magnetic, or photonic devices based on metal oxides, 2D materials, molecular complex and phase change materials, represent important strategies for performing computational tasks with enhanced power efficiency. Here, a special class of memristive materials based on persistent luminescent memitters (termed as a portmanteau of "memory" and "emitter") with optical characteristics closely resembling those of biological synapses is reported. The memory process and synaptic plasticity can be successfully emulated using such memitters under precisely controlled excitation frequency, wavelength, pulse number, and power density. The experimental and theoretical data suggest that electron-coupled trap nucleation and propagation through clustering in persistent luminescent memitters can explain experience-dependent plasticity. The use of persistent luminescent memitters for multichannel image memorization that allows direct visualization of subtle changes in luminescence intensity and realization of short-term and long-term memory is also demonstrated. These findings may promote the discovery of new functional materials as artificial synapses and enhance the understanding of memory mechanisms.
模拟记忆过程，包括编码、存储和检索信息，对于神经形态计算和人工智能至关重要。基于金属氧化物、二维材料、分子配合物和相变材料的电子、磁性或光子设备中的突触行为模拟，代表了通过增强功率效率执行计算任务的重要策略。在这里，报道了一类特殊的基于持久发光发射器的忆阻材料（称为“记忆”和“发射器”的混合词），其光学特性与生物突触非常相似。在精确控制的激发频率、波长、脉冲数和功率密度下，可以使用这种发射器成功模拟记忆过程和突触可塑性。实验和理论数据表明，电子耦合陷阱成核和通过持久发光发射器中的聚类传播可以解释依赖经验的可塑性。还展示了用于多通道图像记忆的持久发光发射器的使用，这允许直接观察发光强度的细微变化，并实现短期和长期记忆。这些发现可能会促进作为人工突触的新型功能材料的发现，并增强对记忆机制的理解。
