• 대한전자공학회논문지SD
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• 제39권3호
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• pp.9-19
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• 2002

본 논문에서는 thermionic emission 모델을 이용하여 SCH 양자우물 레이저 다이오드에 대한 L-I-V특성을 해석적으로 도출하였다. SCH의 bulk 캐리어와 양자우물 속박 캐리어의 관계를 도출하였고, 주입된 전류를 각 영역에서의 캐리어 재결합을 고려한 전류 연속 방정식을 만족하도록 하였다. 또한, high level injection과 전하 중성 조건하에 ambipolar 확산 방정식을 이용하여 캐리어 분포를 고찰하였다. 위 해석적인 모델을 이용하여 계산한 결과, 클래딩 영역의 전위장벽 변화가 전류 전압 특성 변화의 주요 원인으로 나타났다. 또한 thermionic emission에 의한 주입 전류의 forward flux 증가가 캐리어 주입을 증가시키고, 레이저 다이오드의 직렬 저항을 감소시키는 것을 보였다.

• 대한기계학회논문집A
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• 제26권4호
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• pp.775-786
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• 2002

A Mixed Volume and Boundary Integral Equation Method is applied for the effective analysis of elastic wave scattering problems and plane elastostatic problems in unbounded solids containing general anisotropic inclusions and voids or isotropic inclusions. It should be noted that this newly developed numerical method does not require the Green's function for anisotropic inclusions to solve this class of problems since only Green's function for the unbounded isotropic matrix is involved in their formulation for the analysis. This new method can also be applied to general two-dimensional elastodynamic and elastostatic problems with arbitrary shapes and number of anisotropic inclusions and voids or isotropic inclusions. In the formulation of this method, the continuity condition at each interface is automatically satisfied, and in contrast to finite element methods, where the full domain needs to be discretized, this method requires discretization of the inclusions only. Finally, this method takes full advantage of the pre- and post-processing capabilities developed in FEM and BIEM. Through the analysis of plane elastostatic problems in unbounded isotropic matrix with orthotropic inclusions and voids or isotropic inclusions, and the analysis of plane wave scattering problems in unbounded isotropic matrix with isotropic inclusions and voids, it will be established that this new method is very accurate and effective for solving plane wave scattering problems and plane elastic problems in unbounded solids containing general anisotropic inclusions and voids/cracks or isotropic inclusions.