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Abstract Phase change materials, which show different electrical characteristics across the phase transitions, have attracted considerable research attention for their potential electronic device applications. Materials with metal‐to‐insulator or charge density wave (CDW) transitions such as VO2and 1T‐TaS2have demonstrated voltage oscillations due to their robust bi‐state resistive switching behavior with some basic neuronal characteristics. BaTiS3is a small bandgap ternary chalcogenide that has recently reported the emergence of CDW order below 245 K. Here, the discovery of DC voltage / current‐induced reversible threshold switching in BaTiS3devices between a CDW phase and a room temperature semiconducting phase is reported. The resistive switching behavior is consistent with a Joule heating scheme and sustained voltage oscillations with a frequency of up to 1 kHz are demonstrated by leveraging the CDW phase transition and the associated negative differential resistance. Strategies of reducing channel sizes and improving thermal management may further improve the device's performance. The findings establish BaTiS3as a promising CDW material for future electronic device applications, especially for energy‐efficient neuromorphic computing.
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Phase‐Change Materials for Volatile Threshold Resistive Switching and Neuronal Device Applications
Abstract Volatile threshold resistive switching and neuronal oscillations in phase‐change materials, specifically those undergoing ‘metal‐to‐insulator’ transitions, offer unique attributes such as fast and low‐field volatile switching, tunability, and stochastic dynamics. These characteristics are particularly promising for emulating neuronal behaviors and solving complex computational problems. In this review, we summarize recent advances in the development of volatile resistive switching devices and neuronal oscillators based on three representative materials with coincident electronic and structural phase transitions, at different levels of technological readiness: the well‐studied correlated oxide VO2, the charge‐density‐wave transition metal dichalcogenide 1T‐TaS2, and the emerging phase‐change complex chalcogenide BaTiS3. We discuss progresses from the perspective of materials development and device implementation. Finally, we emphasize the major challenges that must be addressed for practical applications of these phase‐change materials and provides outlook on the future research directions in this rapidly evolving field.
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- Award ID(s):
- 2122071
- PAR ID:
- 10647430
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 12
- Issue:
- 42
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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