標題: Terahertz emission and spectroscopy on InN epilayer and nanostructure
作者: Ahn, H.
Pan, C. -L.
Gwo, S.
光電工程學系
Department of Photonics
關鍵字: Indium Nitride;nanostructures;THz emission;THz time-domain spectroscopy;non-Drude model
公開日期: 2009
摘要: We report a comprehensive study on THz emission and spectroscopy of indium nitride (InN) films and its nanorod arrays grown by plasma-assisted molecular beam epitaxy technique. For the enhancement of THz emission from InN, we demonstrated two method; firstly using nanorod arrays, which have large surface area for optical absorption and THz emission, and secondly using nonpolar InN film, of which the electric field is along the sample surface. We propose that a "screened" photo-Dember effect due to narrow surface electron accumulation layer of InN is responsible for the nanorod-size-dependent enhancement from InN nanorods. The primary THz radiation mechanism of nonpolar InN is found to be due to the acceleration of photoexcited carriers under the polarization-induced in-plane electric field. THz time-domain spectroscopy has been used to investigate THz conductivity and dielectric response of InN nanorod arrays and epitaxial film. The complex THz conductivity of InN film is well fitted by the Drude model, while the negative imaginary conductivity of the InN nanorods can be described by using a non-Drude model, which includes a preferential backward scattering due to defects in InN nanorods, or a Coulombic restoring force from charged defects.
URI: http://hdl.handle.net/11536/13067
http://dx.doi.org/10.1117/12.805546
ISBN: 978-0-8194-7462-9
ISSN: 0277-786X
DOI: 10.1117/12.805546
期刊: GALLIUM NITRIDE MATERIALS AND DEVICES IV
Volume: 7216
顯示於類別:會議論文


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