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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
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Polarization-Resolved p-Se/n-WS2 Heterojunctions toward Application in Microcomputer System as Multivalued Signal
Ling Li1, Ge Gao1, Xueting Liu1
1Institute of Semiconductors, South China Normal University, Guangzhou, 510631, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|July 29, 2022
Summary
This study developed novel polarization-sensitive photodetectors using selenium and tungsten disulfide van der Waals heterojunctions. These self-powered devices show promise for advanced optical microcomputer control systems and polarized light applications.
Area of Science:
- Materials Science
- Optoelectronics
- Nanotechnology
Background:
- Polarization-sensitive photodetectors are crucial for polarized light identification and imaging.
- Self-powered signal generators are needed for energy-efficient optical microcomputer control systems (OMCS).
- Van der Waals heterojunctions (vdWH) offer excellent polarization-resolved optoelectronic properties.
Purpose of the Study:
- To develop polarization-sensitive and self-powered photodetectors for OMCS.
- To investigate the optoelectronic properties of p-type selenium (Se) and n-type tungsten disulfide (WS2) vdWH.
- To demonstrate the application of these vdWH devices in multivalued signal triggers for OMCS.
Main Methods:
- Growth of in-plane anisotropic p-type Se flakes.
- Fabrication of type-II vdWH by incorporating Se with n-type WS2.
- Characterization of photodetection performance under 405 nm laser illumination.
- Evaluation of polarization-dependent photocurrent and application in OMCS.
Main Results:
- The p-Se/n-WS2 vdWH exhibited superior photodetection with 3.6% photoelectric conversion efficiency (PCE), 196 mA W-1 responsivity, and 60% external quantum efficiency (EQE).
- The device demonstrated strong in-plane anisotropy, achieving a photocurrent ratio of approximately 2.2, enabling polarized light detection.
- The developed vdWH was successfully applied as a multivalued signal trigger in an optical microcomputer control system.
Conclusions:
- The novel anisotropic vdWH based on Se/WS2 is a promising candidate for polarization-sensitive and self-powered photodetectors.
- This work highlights the potential of vdWH for advanced applications in logic circuits and control systems.
- The findings contribute to the development of next-generation optoelectronic devices for polarized light manipulation and identification.
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