Measurement of Ambipolar Diffusion Coefficient of Photoexcited Carriers with Ultrafast Reflective Grating-Imaging Technique
| Autor: | Xianghai Meng, Sarah C. Mason, Nathanial Sheehan, Ke Chen, Seth R. Bank, Yaguo Wang, Feng He |
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| Rok vydání: | 2017 |
| Předmět: |
Materials science
Physics::Optics 02 engineering and technology Surface finish Grating 01 natural sciences Condensed Matter::Materials Science Optics 0103 physical sciences Electrical and Electronic Engineering Diffusion (business) 010306 general physics Diffraction grating Quantum well Condensed Matter::Other business.industry Ambipolar diffusion Scattering Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 021001 nanoscience & nanotechnology Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials Optoelectronics 0210 nano-technology business Ultrashort pulse Biotechnology |
| Zdroj: | ACS Photonics. 4:1440-1446 |
| ISSN: | 2330-4022 |
| DOI: | 10.1021/acsphotonics.7b00187 |
| Popis: | A novel ultrafast reflective grating-imaging technique has been developed to measure ambipolar carrier diffusion in GaAs/AlAs quantum wells and bulk GaAs. By integrating a transmission grating and an imaging system into the traditional pump–probe setup, this technique can acquire carrier diffusion properties conveniently and accurately. The fitted results of the diffusion coefficient and diffusion length in bulk GaAs agree well with the literature values obtained by other techniques. The diffusion coefficient and diffusion length of GaAs/AlAs quantum wells are found to increase with the well layer thickness, which suggests that interface roughness scattering dominates carrier diffusion in GaAs/AlAs quantum wells. With the advantages of simple operation, sensitive detection, rapid and nondestructive measurement, and extensive applicability, the ultrafast reflective grating-imaging technique has great potential in experimental study of carrier diffusion in various materials. |
| Databáze: | OpenAIRE |
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