Yim Haena, Yoon Chansoo, Ryu Ahrom, Yoo So Yeon, Kwon Ju Young, Oh Gwangtaek, Kim Sohwi, Kee Eun Hee, Chae Keun Hwa, Yoon Jung Ho, Park Bae Ho, Choi Ji-Won
Center for Electronic Materials, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea.
Division of Quantum Phases and Devices, Department of Physics, Konkuk University, Seoul 05029, Republic of Korea.
Nano Lett. 2023 Jul 26;23(14):6360-6368. doi: 10.1021/acs.nanolett.3c01057. Epub 2023 Jul 6.
Vertical two-terminal synaptic devices based on resistive switching have shown great potential for emulating biological signal processing and implementing artificial intelligence learning circuitries. To mimic heterosynaptic behaviors in vertical two-terminal synaptic devices, an additional terminal is required for neuromodulator activity. However, adding an extra terminal, such as a gate of the field-effect transistor, may lead to low scalability. In this study, a vertical two-terminal Pt/bilayer SrAgNbO (SANO) nanosheet/Nb:SrTiO (Nb:STO) device emulates heterosynaptic plasticity by controlling the number of trap sites in the SANO nanosheet via modulation of the tunneling current. Similar to biological neuromodulation, we modulated the synaptic plasticity, pulsed pair facilitation, and cutoff frequency of a simple two-terminal device. Therefore, our synaptic device can add high-level learning such as associative learning to a neuromorphic system with a simple cross-bar array structure.
