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Observation of strong anisotropic forbidden transitions in (001) InGaAs/GaAs single-quantum well by reflectance-difference spectroscopy and its behavior under uniaxial strain.

Yu JL, Chen YH, Tang CG, Jiang C, Ye XL - Nanoscale Res Lett (2011)

Bottom Line: The strong anisotropic forbidden transition has been observed in a series of InGaAs/GaAs single-quantum well with well width ranging between 3 nm and 7 nm at 80 K.Numerical calculations within the envelope function framework have been performed to analyze the origin of the optical anisotropic forbidden transition.It is found that the optical anisotropy of this transition can be mainly attributed to indium segregation effect.

View Article: PubMed Central - HTML - PubMed

Affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, P,O, Box 912, Beijing 100083, People's Republic of China. yhchen@semi.ac.cn.

ABSTRACT
The strong anisotropic forbidden transition has been observed in a series of InGaAs/GaAs single-quantum well with well width ranging between 3 nm and 7 nm at 80 K. Numerical calculations within the envelope function framework have been performed to analyze the origin of the optical anisotropic forbidden transition. It is found that the optical anisotropy of this transition can be mainly attributed to indium segregation effect. The effect of uniaxial strain on in-plane optical anisotropy (IPOA) is also investigated. The IPOA of the forbidden transition changes little with strain, while that of the allowed transition shows a linear dependence on strain.PACS 78.66.Fd, 78.20.Bh, 78.20.Fm.

No MeSH data available.


Related in: MedlinePlus

Schematic drawing of the uniaxial strain apparatus.
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Figure 1: Schematic drawing of the uniaxial strain apparatus.

Mentions: In order to study the effect of uniaxial strain on the IPOA, we cleaved the sample with well width 5 nm into a 25 × 4 mm2 strip. Uniaxial strain was introduced by a stress device as shown in Figure 1 which is the same as the one used by Papadimitriou and Richter [15]. When the length-to-width ratio is greater than 3, the strip behaves like a bend rod, and the apparatus produces only two nonzero strain components:ϵx'x' (tensile) ϵz'z' and (compressive). Here x' and y' are along the cleavage axis [110] and [110] as shown in Figure 1. Transformed to the principal axis [100] and [010], the nonzero strain components are ϵxx, ϵyy, ϵzz and ϵxy [4], and only ϵxy will introduce IPOA. The maximum strain component ϵxy at the center of the strip is given by [16]


Observation of strong anisotropic forbidden transitions in (001) InGaAs/GaAs single-quantum well by reflectance-difference spectroscopy and its behavior under uniaxial strain.

Yu JL, Chen YH, Tang CG, Jiang C, Ye XL - Nanoscale Res Lett (2011)

Schematic drawing of the uniaxial strain apparatus.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211267&req=5

Figure 1: Schematic drawing of the uniaxial strain apparatus.
Mentions: In order to study the effect of uniaxial strain on the IPOA, we cleaved the sample with well width 5 nm into a 25 × 4 mm2 strip. Uniaxial strain was introduced by a stress device as shown in Figure 1 which is the same as the one used by Papadimitriou and Richter [15]. When the length-to-width ratio is greater than 3, the strip behaves like a bend rod, and the apparatus produces only two nonzero strain components:ϵx'x' (tensile) ϵz'z' and (compressive). Here x' and y' are along the cleavage axis [110] and [110] as shown in Figure 1. Transformed to the principal axis [100] and [010], the nonzero strain components are ϵxx, ϵyy, ϵzz and ϵxy [4], and only ϵxy will introduce IPOA. The maximum strain component ϵxy at the center of the strip is given by [16]

Bottom Line: The strong anisotropic forbidden transition has been observed in a series of InGaAs/GaAs single-quantum well with well width ranging between 3 nm and 7 nm at 80 K.Numerical calculations within the envelope function framework have been performed to analyze the origin of the optical anisotropic forbidden transition.It is found that the optical anisotropy of this transition can be mainly attributed to indium segregation effect.

View Article: PubMed Central - HTML - PubMed

Affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, P,O, Box 912, Beijing 100083, People's Republic of China. yhchen@semi.ac.cn.

ABSTRACT
The strong anisotropic forbidden transition has been observed in a series of InGaAs/GaAs single-quantum well with well width ranging between 3 nm and 7 nm at 80 K. Numerical calculations within the envelope function framework have been performed to analyze the origin of the optical anisotropic forbidden transition. It is found that the optical anisotropy of this transition can be mainly attributed to indium segregation effect. The effect of uniaxial strain on in-plane optical anisotropy (IPOA) is also investigated. The IPOA of the forbidden transition changes little with strain, while that of the allowed transition shows a linear dependence on strain.PACS 78.66.Fd, 78.20.Bh, 78.20.Fm.

No MeSH data available.


Related in: MedlinePlus