Enhanced terahertz radiation from high stacking fault density nonpolar GaN.
- Resource Type
- Article
- Authors
- Metcalfe, Grace D.; Shen, Hongen; Wraback, Michael; Hirai, Asako; Wu, Feng; Speck, James S.
- Source
- Applied Physics Letters. 6/16/2008, Vol. 92 Issue 24, p241106. 3p. 1 Diagram, 3 Graphs.
- Subject
- *TERAHERTZ technology
*DENSITY
*WURTZITE
*ELECTRIC fields
*POLARIZATION (Electricity)
*PULSE (Heart beat)
*GALLIUM
*NITROGEN
- Language
- ISSN
- 0003-6951
Terahertz emission from high stacking fault density m-GaN has been observed using ultrafast pulse excitation. The terahertz signal exhibits a 360° periodicity with sample rotation and a polarity flip at 180°, characteristic of real carrier transport in an in-plane electric field parallel to the c axis induced by stacking fault (SF)-terminated internal polarization at wurtzite domain boundaries. The terahertz emission can be enhanced by several times relative to that from a SF-free m-GaN sample, for which the terahertz signal emanates from surface surge currents and diffusion-driven carrier transport normal to the surface and is independent of the c-axis orientation. [ABSTRACT FROM AUTHOR]