Three-Terminal Ovonic Threshold Switch (3T-OTS) with Tunable Threshold Voltage for Versatile Artificial Sensory Neurons

Hyejin Lee, Seong Won Cho, Seon Jeong Kim, Jaesang Lee, Keun Su Kim, Inho Kim, Jong Keuk Park, Joon Young Kwak, Jaewook Kim, Jongkil Park, Yeon Joo Jeong, Gyu Weon Hwang, Kyeong Seok Lee, Daniele Ielmini, Suyoun Lee

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


Inspired by information processing in biological systems, sensor-combined edge-computing systems attract attention requesting artificial sensory neurons as essential ingredients. Here, we introduce a simple and versatile structure of artificial sensory neurons based on a novel three-terminal Ovonic threshold switch (3T-OTS), which features an electrically controllable threshold voltage (Vth). Combined with a sensor driving an output voltage, this 3T-OTS generates spikes with a frequency depending on an external stimulus. As a proof of concept, we have built an artificial retinal ganglion cell (RGC) by combining a 3T-OTS and a photodiode. Furthermore, this artificial RGC is combined with the reservoir-computing technique to perform a classification of chest X-ray images for normal, viral pneumonia, and COVID-19 infections, releasing the recognition accuracy of about 86.5%. These results indicate that the 3T-OTS is highly promising for applications in neuromorphic sensory systems, providing a building block for energy-efficient in-sensor computing devices.

Original languageEnglish
Pages (from-to)733-739
Number of pages7
JournalNano letters
Issue number2
Publication statusPublished - 2022 Jan 26

Bibliographical note

Publisher Copyright:
© 2022 American Chemical Society

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • General Chemistry
  • General Materials Science
  • Condensed Matter Physics
  • Mechanical Engineering


Dive into the research topics of 'Three-Terminal Ovonic Threshold Switch (3T-OTS) with Tunable Threshold Voltage for Versatile Artificial Sensory Neurons'. Together they form a unique fingerprint.

Cite this