Tuning Resistive Switching Behavior by Controlling Internal Ionic Dynamics for Biorealistic Implementation of Synaptic Plasticity
Tuning Resistive Switching Behavior by Controlling Internal Ionic Dynamics for Biorealistic Implementation of Synaptic Plasticity
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DOI：
10.1002/aelm.202101025
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发表时间：
2022-02
影响因子：
6.2
通讯作者：
Sangmin Yoo;Yuting Wu;Yongmo Park;Wei D. Lu
中科院分区：
文献类型：
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作者：
Sangmin Yoo;Yuting Wu;Yongmo Park;Wei D. Lu
记忆装置已经显示出丰富的转换行为，这些行为与突触功能非常相似，并为构建高效的神经形态系统提供了基础。结果表明，阻性开关效应不仅受控于外场，而且受控于促进离子过程的各种内部状态变量的动力学。例如，内部温度作为第二状态变量来调节离子运动，并为基于定时和速率的学习规则(如脉冲定时相关塑性(STDP))的本地实现提供内部定时机制。这项工作表明，Ta2O5基忆阻器中的第二个状态变量，即其内部温度，可以通过调节材料性质和器件结构来系统地设计，从而得到具有不同时间常数的可调的STDP特性。当与人工突触后神经元结合时，二阶忆阻器突触可以自发地捕捉输入流事件中的时间相关性。
Memristive devices have demonstrated rich switching behaviors that closely resemble synaptic functions and provide a building block to construct efficient neuromorphic systems. It is demonstrated that resistive switching effects are controlled not only by the external field, but also by the dynamics of various internal state variables that facilitate the ionic processes. The internal temperature, for example, works as a second‐state variable to regulate the ion motion and provides the internal timing mechanism for the native implementation of timing‐ and rate‐based learning rules such as spike timing dependent plasticity (STDP). In this work, it is shown that the 2nd state‐variable in a Ta2O5‐based memristor, its internal temperature, can be systematically engineered by adjusting the material properties and device structure, leading to tunable STDP characteristics with different time constants. When combined with an artificial post‐synaptic neuron, the 2nd‐order memristor synapses can spontaneously capture the temporal correlation in the input streaming events.