1. Intersubband absorption with difference-frequency generation in GaAs asymmetric quantum wells.
- Author
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Cao Xiao-Long, Li Zhong-Yang, Yao Jian-Quan, Wang Yu-Ye, Zhu Neng-Nian, Zhong Kai, and Xu De-Gang
- Subjects
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GALLIUM arsenide , *LIGHT absorption , *RADIO frequency , *QUANTUM wells , *SUBMILLIMETER waves , *WAVELENGTHS - Abstract
An asymmetric quantum well (AQW) is designed to emit terahertz (THz) waves by using difference frequency generation (DFG) with the structure of GaAs/Al0:2Ga0:8As/Al0:5Ga0:5As. The characteristics of absorption coefficients are analysed under the parabolic and non-parabolic energy-band conditions in detail. We find that the absorption coefficients vary with the two pump optical intensities, and they reach the maxima when the pump wavelengths are given as p1 = 9:70 m and p2 = 10:64 m, respectively. Compared with non-parabolic conditions, the total absorption coefficient under parabolic conditions shows a blue shift, which is due to the increase in the energy difference between the ground and excited states. By adjusting the two pump optical intensities, the wave vector phase-matching condition inside the AQW is satisfied. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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