InGaAs量子点的自发发射及光增益

研究了InGaAs量子点材料自发发射、放大自发发射及光增益特性.实验发现InGaAs量子点材料随着注入电流密度的增加,其自发发射及放大自发发射光谱峰蓝移,表现出明显的能带填充现象.由于量子点材料尺寸及形状等存在一定的分布,在光谱中没有明显的对应量子点激发态的谱峰.由单程增益放大自发发射得到了量子点材料在不同注入电流密度下的光增益谱.结果表明存在由于量子点大小分布造成的量子点态非均匀展宽引起的增益峰蓝移和增益谱展宽现象.

Spontaneous Emission and Optical Gain in InGaAs Quantum Dots

The spontaneous emission,amplified spontaneous emission and optical gain in In Ga As quantum dots are investigat- ed.The peak wavelength of spontaneous em ission spectra and amplified spontaneous emission spectra exhibit blue shift with increasing of the injected current density,indicating distinctive band filling effect.No distinctive isolated states are observed in the spectra due to the inhom ogeneous broadening of the dot states related to the distribution of the size and the shape of the quantum dots.The net modal gain spectra are obtained by single- pass amplified spontaneous em ission spectra at different in- jected current densities.The blue shift of the gain peak and broadening of the gain spectra are observed.