研究了 In Ga As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 In Ga As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 ,...研究了 In Ga As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 In Ga As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 .展开更多
Optically pumped stimulated emission behavior was demonstrated in a slab waveguide structure formed by substrate/organic film/air. The organic film was deposited by high vacuum (1×10 -3 Pa) co evaporating of 8 hy...Optically pumped stimulated emission behavior was demonstrated in a slab waveguide structure formed by substrate/organic film/air. The organic film was deposited by high vacuum (1×10 -3 Pa) co evaporating of 8 hydroxyquinolinato aluminum(Alq) and laser dye DCM. A wafer of quartz was used as the substrate. The thickness of the organic film was about 300nm, and the percentage of DCM was about 3%. The third harmonic output(355nm) of a Nd∶YAG laser was used as the excitation source. The pulse width was about 300ps. The repetition rate was 2Hz. The pump beam was focused onto the sample with a cylindrical lens ( f =10cm). The excitation area was a typical 10mm×0 2mm stripe. Detected from the side or the surface of the organic film, the fluorescence spectrum with the FWHM (the full width at half maximum) of about 110nm was achieved at excitation pulses energy of 0 1μJ. Increasing the excitation pulse energy to 4μJ, the FWHM of the spectrum detected from the edge of the sample reduced to 13nm with the peak at 620nm and the spectrum from the surface was still a broad band. The change of the emission spectra detected from the edge of the sample showed a clear threshold action and gain narrowing phenomenon when increasing the excitation intensity. The spectrally gain narrowing results from the amplified spontaneous emission (ASE) of the waveguide along the excitation stripe in the film.展开更多
文摘研究了 In Ga As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 In Ga As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 .
文摘Optically pumped stimulated emission behavior was demonstrated in a slab waveguide structure formed by substrate/organic film/air. The organic film was deposited by high vacuum (1×10 -3 Pa) co evaporating of 8 hydroxyquinolinato aluminum(Alq) and laser dye DCM. A wafer of quartz was used as the substrate. The thickness of the organic film was about 300nm, and the percentage of DCM was about 3%. The third harmonic output(355nm) of a Nd∶YAG laser was used as the excitation source. The pulse width was about 300ps. The repetition rate was 2Hz. The pump beam was focused onto the sample with a cylindrical lens ( f =10cm). The excitation area was a typical 10mm×0 2mm stripe. Detected from the side or the surface of the organic film, the fluorescence spectrum with the FWHM (the full width at half maximum) of about 110nm was achieved at excitation pulses energy of 0 1μJ. Increasing the excitation pulse energy to 4μJ, the FWHM of the spectrum detected from the edge of the sample reduced to 13nm with the peak at 620nm and the spectrum from the surface was still a broad band. The change of the emission spectra detected from the edge of the sample showed a clear threshold action and gain narrowing phenomenon when increasing the excitation intensity. The spectrally gain narrowing results from the amplified spontaneous emission (ASE) of the waveguide along the excitation stripe in the film.
