The equilibrium composition in strained quantum dot is the result of both elastic relaxation and chemical mixing effects, which have a direct relationship to the optical and electronic properties of the quantum-dot-ba...The equilibrium composition in strained quantum dot is the result of both elastic relaxation and chemical mixing effects, which have a direct relationship to the optical and electronic properties of the quantum-dot-based device. Using the method of moving asymptotes and finite element tools, an efficient technique has been developed to compute the composition profile by minimising the Gibbs free energy in self-assembled alloy quantum dot. In this paper, the composition of dome-shaped CexSi1-x/Si quantum dot is optimized, and the contribution of the different energy to equilibrium composition is discussed. The effect of composition on the critical size for shape transition of pyramid-shaped GeSi quantum dot is also studied.展开更多
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2009AA03Z405)the National Natural Science Foundation of China(Grant Nos.60908028,60971068,10979065,and 10947150)the High School Innovation and Introducing Talent Project of China(Grant No.B07005)
文摘The equilibrium composition in strained quantum dot is the result of both elastic relaxation and chemical mixing effects, which have a direct relationship to the optical and electronic properties of the quantum-dot-based device. Using the method of moving asymptotes and finite element tools, an efficient technique has been developed to compute the composition profile by minimising the Gibbs free energy in self-assembled alloy quantum dot. In this paper, the composition of dome-shaped CexSi1-x/Si quantum dot is optimized, and the contribution of the different energy to equilibrium composition is discussed. The effect of composition on the critical size for shape transition of pyramid-shaped GeSi quantum dot is also studied.
