InP/InGaAsP多量子阱自发辐射谱的解析函数

利用洛伦兹线型函数、高斯线型函数和Sech线型函数对InP/InGaAsP多量子阱自发辐射谱进行拟合,采用莱文贝格-马夸特算法,得到上述三种函数的解析表达式.研究结果表明:高斯线型光谱拟合函数的中心波长为1548.651nm,谱线半极大全宽度为61.42 nm,功率补偿为0.00212 mW,拟合优度为0.99191,残差平方和为2.26505×10~(-6).高斯线型拟合的拟合优度最大,残差平方和最小,且各数据点的残差值分布在±0.0001之间,分布比较均匀.高斯线型函数具有较高拟合度.

Analytic function for spontaneous emission spectrum of InP/InGaAsP multi-quantum wells

The analytic function for the amplified spontaneous emission spectrum of InP/InGaAsP multi-quantum wells is studied by spectrum fitting. Three fitting functions, Lorentz, Gaussian and Sech line shape functions are chosen, and the analytical expressions for the above three functions are obtained with Levenberg-Marquardt algorithm, respectively. The center wavelength of Lorentz line shape function spectrum fitting is 1548.707 nm with 66.23 nm of full-width half maximum (FWHM), -0.00036484 mW power compensation, 0.98294 of R-square and 4.76743×10^-6 of residual sum of squares; the center wavelength of Gaussian line shape function spectrum fitting is 1548.651 nm with 61.42 nm of FWHM, 0.00212 mW power compensation, 0.99191 of R-square and 2.26505×10^-6 of residual sum of squares; the center wavelength of Sech line shape function spectrum fitting is 1548.787 nm with 36.99 nm of FWHM, 0.00222 mW power compensation, 0.98128 of R-square and 5.24331×10^-6 of residual sum of squares. It can be seen that Gaussian line shape function spectrum fitting has the highest R-square and smallest residual sum of squares, and the residual squares of data are symmetrically distributed among ±0.0001. Gaussian line shape function spectrum fitting has higher fitting degree. It is demonstrated that InP/InGaAsP multi-quantum wells is a kind of active layer quantum well structure semiconductor material, whose amplified spontaneous emission spectrum line shape belongs to inhomogeneous broadening due to the effect of lattice defects, the corresponding line shape function is Gaussian line shape function, and the amplified spontaneous emission spectrum line shape function can be used for designing the optical passive devices.