Division of Quantum Phases & Devices, Department of Physics, Konkuk University , Seoul 143-701, Korea.
School of Electrical Engineering, Kookmin University , Seoul 136-702, Korea.
Nano Lett. 2017 Mar 8;17(3):1949-1955. doi: 10.1021/acs.nanolett.6b05308. Epub 2017 Feb 24.
Selectively activated inorganic synaptic devices, showing a high on/off ratio, ultrasmall dimensions, low power consumption, and short programming time, are required to emulate the functions of high-capacity and energy-efficient reconfigurable human neural systems combining information storage and processing ( Li et al. Sci. Rep. 2014 , 4 , 4096 ). Here, we demonstrate that such a synaptic device is realized using a Ag/PbZrTiO (PZT)/LaSrMnO (LSMO) ferroelectric tunnel junction (FTJ) with ultrathin PZT (thickness of ∼4 nm). Ag ion migration through the very thin FTJ enables a large on/off ratio (10) and low energy consumption (potentiation energy consumption = ∼22 aJ and depression energy consumption = ∼2.5 pJ). In addition, the simple alignment of the downward polarization in PZT selectively activates the synaptic plasticity of the FTJ and the transition from short-term plasticity to long-term potentiation.
选择性激活的无机突触器件，具有高导通-关断比、超小尺寸、低功耗和短编程时间，是模拟具有信息存储和处理功能的高容量、高能效可重构人类神经系统所必需的（Li 等人，Sci. Rep. 2014 ，4 ，4096）。在这里，我们证明了使用 Ag/PbZrTiO（PZT）/LaSrMnO（LSMO）铁电隧道结（FTJ）可以实现这种突触器件，其 PZT 非常薄（厚度约为 4nm）。Ag 离子通过非常薄的 FTJ 的迁移使得导通-关断比（10）和能量消耗（增强能量消耗=22aJ，抑制能量消耗=2.5pJ）都很大。此外，PZT 中向下极化的简单排列选择性地激活了 FTJ 的突触可塑性，以及从短期可塑性到长期增强的转变。
