Conduction channel configuration controlled digital and analog response in TiO2-based inorganic memristive artificial synapses

Abstract

The operating current regime is found to play a key role in determining the synaptic characteristic of memristor devices. A conduction channel that is formed using high current compliance prior to the synaptic operation results in digital behavior; the high current stimulus forms a complete conductive filament connecting the cathode and anode, and the high electric field promotes abrupt redox reactions during potentiation and depression pulsing schemes. Conversely, the conduction can be reconfigured to produce a filamentary-homogeneous hybrid channel by utilizing the low current stimulus, and this configuration enables the occurrence of analog behavior. The capabilities of memristors showing programmable digital-to-analog or analog-to-digital transformation open a wide range of applications in electronics. We propose a conduction mechanism to explain this phenomenon.

A Digital–Analog Integrated Memristor Based on a ZnO NPs/CuO NWs Heterostructure for Neuromorphic Computing

“…To reduce the complexity of the memristor circuit and its operation, the development of a digital–analog integrated memristor is critical in developing neuromorphic computing systems. Recently, several works have reported efforts to realize a digital-to-analog transition in a memristive system. − For instance, Kim et al reported the transition between digital and analog behavior in a NiO x -based memristor . However, rather than in situ control, this digital-to-analog transition was achieved by regulating the oxygen vacancy content of NiO during the preparation process, which cannot accomplish the coexistence of digital and analog states in a single device, thus limiting its practical applications.…”

Amorphous ITZO-Based Selector Device for Memristor Crossbar Array

“…Memristor and memristive circuit are one of the candidates for the advanced computing architecture which differs from the conventional von Neumann architecture suffering from data movement between the central processing unit and memory. The memristor has been widely developed for promising nonvolatile memory and artificial synapse device due to its simple two-terminal structure, fast switching speed, and low power consumption [ 1 , 2 , 3 , 4 , 5 ]. In addition, memristive circuit can implement a nonvolatile logic-in-memory circuit that enables normally off computing [ 6 , 7 , 8 , 9 ].…”