The emergence of 2D ferroelectrics offers a promising path to implement next-generation information technology, including digital memory and analog computing. Here, it is demonstrated that digital or analog memory can be achieved in a single crossbar type two-terminal (Au-Ti) α-In₂Se₃ device depending on the driving voltage. The analog operation is enabled by ferroelectric polarization-modulated Schottky barrier, while resistive filament switching drives the digital operation. By tuning ferroelectric properties, multiple analog conductance states can be obtained for mimicking various synaptic behaviors like excitatory postsynaptic current, inhibitory postsynaptic current, potentiation/depression and spiking-timing-dependent plasticity. A simulated neural network built from these synaptic devices shows good on-line learning accuracy (≈93.2%) for digital recognition of handwriting. Based on filament formation/rupture mechanism, α-In₂Se₃ devices also exhibits excellent digital memory performance with large on/off ratio (>10³), high on-current density (10⁵ A cm⁻²) and fast switching speed (≈10 ns). The combination of analog and digital memory modes in two-terminal α-In₂Se₃ devices is useful in highly dense and complex electronics.

中文翻译：

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用于神经形态和记忆应用的模拟和数字模式 α-In2Se3 忆阻器件

二维铁电体的出现为实现包括数字存储器和模拟计算在内的下一代信息技术提供了一条有前途的途径。在这里，证明了数字或模拟存储器可以在单个交叉型两端 (Au-Ti) α-In ₂ Se _{3 中实现}器件取决于驱动电压。模拟操作由铁电极极化调制肖特基势垒实现，而电阻丝开关驱动数字操作。通过调整铁电特性，可以获得多种模拟电导状态来模拟各种突触行为，如兴奋性突触后电流、抑制性突触后电流、增强/抑制和尖峰时间依赖性可塑性。由这些突触设备构建的模拟神经网络显示出良好的在线学习准确率 (≈93.2%)，用于手写数字识别。基于细丝形成/断裂机制，α-In ₂ Se ₃器件还表现出优异的数字存储性能和大开/关比（>10 ³)、高导通电流密度 (10 ⁵ A cm ^-2 ) 和快速开关速度 (≈10 ns)。两端 α-In ₂ Se ₃器件中模拟和数字存储模式的组合在高密度和复杂的电子产品中非常有用。