Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Observation of strong anisotropic forbidden transitions in (001) InGaAs/GaAs single-quantum well by reflectance-difference spectroscopy and its behavior under uniaxial strain | Yu et al. Nanoscale Research Letters 2011 6 210 http content 6 1 210 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Observation of strong anisotropic forbidden transitions in 001 InGaAs GaAs single-quantum well by reflectance-difference spectroscopy and its behavior under uniaxial strain Jin-Ling Yu Yong-Hai Chen Chen-Guang Tang ChongYun Jiang Xiao-Ling Ye 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 Introduction It is well known that in-plane optical anisotropy IPOA can be introduced in a 001 -grown zinc-blende quantum well QW when the symmetry is reduced from D2d to C2u 1-6 . There are two kinds of symmetry reduction effect SRE one is bulk SRE and the other is interface SRE 2 4 . The bulk SRE can be introduced by electric field compositional variation across the QW and uniaxial strain 7-10 . The IPOA induced by uniaxial strain in GaAs AlxGa1-xAs QWs has been reported by Shen 10 Rau 8 and Tang 11 . However as far as we know this effect in InxGa1-xAs GaAs QW has never been reported. The interface SRE which origins from C2v symmetry of a 001 zinc-blende interface can be introduced by special interface chemical bonds segregation effect and the anisotropic interface structures 2 3 6 . It was found that the interface-induced IPOA was very strong in the QWs sharing .
