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Updated: Jun 16, 2025

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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
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Non-volatile and multistate terahertz response in semi-floating-gate graphene field-effect transistors
Optics Express
|June 14, 2025
Summary
We developed a terahertz (THz) detector using a graphene/h-BN/graphene semi-floating gate (SFG) structure. This device shows memory and controllable photothermoelectric (PTE) THz response, enabling sensing, storage, and processing.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Optoelectronics
Background:
- Two-dimensional (2D) materials offer unique electronic and optical properties for advanced device applications.
- Semi-floating gate (SFG) structures enable integration of sensing, storage, and processing functionalities.
- Terahertz (THz) technology requires efficient detectors for diverse applications.
Purpose of the Study:
- To demonstrate a multifunctional photodetector based on a 2D material SFG structure.
- To investigate the memory and photothermoelectric (PTE) response characteristics of the device.
- To provide insights into the optoelectronic behavior of SFG-FETs for future applications.
Main Methods:
- Fabrication of a graphene/h-BN/graphene SFG structure for THz detection.
- Experimental characterization of the device's memory and gate-controlled THz response.
- Development of a theoretical model to analyze the observed optoelectronic phenomena.
Main Results:
- The SFG-based THz detector exhibited excellent memory behavior.
- A gate-controlled, non-volatile, and multistate photothermoelectric (PTE) THz response was achieved.
- Theoretical model results showed good agreement with experimental data.
Conclusions:
- The demonstrated 2D material SFG photodetector integrates sensing, storage, and processing capabilities.
- The device's complex optoelectronic behavior, including memory and PTE effects, was elucidated.
- This work advances the development of multifunctional photodetectors for THz applications.
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