金属纳米颗粒-光(磁)敏蛋白质分子体系的忆阻效应及光(慢磁)调控研究

A memristor (memory resistor) is a nonlinear resistor and is called as the fourth basic circuit element whose resistance remembers all past voltages. The characteristic of data processing devices can be significantly improved when memristors are integrated with transistors into a circuit. Since Williams’ group at HP Labs succeeded in fabricating a memristor prototype in 2008, many groups have been interested in this field. Compared to the inorganic memory technology, the organic memory device has the advantages of low cost, high flexibility and versatile functionality, and is more suitable for large area fabricated. But the effects of light and magnetic field on the memristive characteristics have not been reported. In the present project, we will fabricate a seris of Organic thin film system with mono-dispersed metal nanoparticles by choosing photo- (magnetic-) sensitive protein. The memristive properites of device can be improved by the change of local electric field on the surface of nanoparticles. The energy state distribution and charge transfer rate can be changed by the surface plasmon resonance effects. The effects of different frequency light and magnetic field on memristor characteristics will be studied and the regulation of memristive properites will be achieved by laser and slow magnetic. The convenient method for preparing the high properties, high stability and cost-effective memristor will be obtained. Based on the experimental results, we will give the Hamiliton of system and studied the memristive mechanism by combined simulation calculation. The obtained results will provide a reference for the development of the artificial neural network similar to human brain.

忆阻器是具有记忆效应的非线性电阻，被称为第四个基本电路元件，集成在电路中可以大幅度提高数据处理器的性能。自从2008年William's团队构建出忆阻器的原型后，国际上就掀起了记忆电阻的研究热潮，其中有机忆阻器因其低成本、易制备等优点备受关注，但光和磁对忆阻性能的影响未见报道。本课题拟选择光(磁)敏蛋白质分子材料，采用原位合成和自组装方法制备含有单分散金属纳米颗粒的有机薄膜，利用纳米颗粒的表面效应改变局域电场，实现对电荷的入陷和脱陷，提高记忆特性，构建具有高忆阻性能的纳米组装体系；利用金属纳米颗粒表面等离子体共振效应改变分子能态分布和电荷传输速率，研究不同频率的光和磁对忆阻器特性的影响，实现激光和慢磁对忆阻器性能的调控，探讨高性能、低成本忆阻器的简易合成方法；根据纳米组装体系的结构特点和实验规律，构建忆阻元件系统的哈密顿量,研究其记忆机理。

经过4年多的努力工作，我们课题组完成了国家自然科学基金资助项目（61574071）。首先，利用具有供体和受体结构的共聚物来构建了兼具记忆电阻和记忆电容特性的有机电子器件，获得了与单电阻状态下的记忆电容特性，实现了双参数存储。该器件具有与三种电阻对应的六种电容状态以及优良的存储切换特性，包括低开/关电压、较长的保持时间和一次写入-多次读取和写入-读取-擦除-读取能力。第二，研究了不同激光照射对器件忆阻性能的影响，激光照射20 s后负压区域的电流走向发生反转，器件的开关特性由双极转变为单极。照射60 s后器件电流走向发生了反转，开/关电压降低到-2.2/1.3 V，高低电阻比提高到104；电流降低了一个量级，且I-V曲线的涨落减小，有效降低了功耗，提高了数据读取的准确性和稳定性。第三，通过引入分子内部极化算符, 建立了记忆电阻和记忆电容的关联性, 给出了描述器件双参量多状态特征的矩阵模型。第四，研究了基于有机共聚物记忆电容器的新型人工突触，在0.1V低工作电压下实现了良好的突触可塑性，包括双脉冲易化、增强和抑制行为，灵敏度可达50mV，与人脑中产生突触可塑性的动作电位一致；同时实现了从短时程可塑性向长时程可塑性的转变和学习-遗忘-再学习行为。第五，研究了生长在PMN-PT(0 1 1)基板上的楔形铂/钴/铂夹芯中三层垂直磁各向异性的电操纵和单晶 Co/Pt 双层中异常的角相关磁阻效应。第六，利用纳米结构的等离子体效应研究了三维云状铝层纳米结构的红外SERS谱以及应用。第七，研究了醋酸锌溶液表面改性对ZnAl2O4:Cr3+颗粒结构和光学性能的影响。第八，研究了Ag 纳米颗粒嵌入鸡蛋蛋白生物器件对记忆行为的调控，纳米银粒子引入后，记忆电阻转化为双极性，耐久性能提高，电阻开关电压降低。这些结果为提高存储密度和信息加密的安全性、降低功耗、研制高灵敏度的人工突触提供了有力的参考。