Robust Hot-Carrier-Based Gallium Arsenide Photodetectors for 2 µm Optical Window
Journal
Advanced Optical Materials
ISSN
21951071
Date Issued
2026
Author(s)
Liu, Ming-Chen
Phan, Mun-Wei
Mohanty, Sheetikanta
Tseng, Po-Hsien
Hsieh, Wei-Chi
Chen, Szu-Hung
Lai, Yu-Sheng
Abstract
Recent advancements in fiber-optic communication have established the conventional wavelength of 1550 nm. However, the next generation of telecommunications promises excellent prospects at 2 µm wavelengths via hollow-core photonic-bandgap fibers (HC-PBGFs). Nevertheless, many semiconductors struggle to operate effectively at their intrinsic bandgap due to wavelength redshift. In this work, the gallium arsenide (GaAs) operating band is successfully extended to the 2 µm optical communication band using the GaAs Trench Metal (GATM) structure, enhancing absorptance and overall performance. Notably, the GATM device exhibits a photovoltage responsivity of 5.48 V W−1 under zero bias operation. This remarkable performance is attributed to the surface plasmonic effect and resonant cavity mode, resulting in approximately 3.8 times current gain and about 3 times voltage gain compared to flat film devices. Furthermore, the GATM devices demonstrate exceptional temperature stability, ranging from −195°C to 195°C, highlighting their potential for applications in harsh environments. These devices showcase stable and improved performance wiin the 2 µm optical communication band, ensuring reliable operation across a broad temperature range. Such characteristics make them well-suited for advanced telecommunications technologies.
Subjects
2 µm optical window
harsh environment
hot carriers
optical communication band
photodetection
Schottky junction
surface plasmon resonance
Publisher
John Wiley and Sons Inc
Type
journal article