CAJ | 학술논문

根据光波导理论,采用数值方法分析了单模锥形光纤锥区传输常数和光场分布的变化情况.采用分步傅里叶法数值求解广义的非线性薛定谔方程,对超短脉冲在锥区的传输演化进行了研究.结果表明:传输常数沿拉锥方向缓慢减小,在拉锥末端迅速减小;在拉锥初始阶段,能量主要集中在纤芯中,"转换点"之后能量在纤芯和包层中重新分布,光强在拉锥末端变强;脉宽小于80 fs的超短脉冲沿锥区传输时,沿拉锥方向,脉冲不断展宽,而当脉宽大于80 fs时,脉冲展宽不明显.
근거광파도이론,채용수치방법분석료단모추형광섬추구전수상수화광장분포적변화정황.채용분보부리협법수치구해엄의적비선성설정악방정,대초단맥충재추구적전수연화진행료연구.결과표명:전수상수연랍추방향완만감소,재랍추말단신속감소;재랍추초시계단,능량주요집중재섬심중,"전환점"지후능량재섬심화포층중중신분포,광강재랍추말단변강;맥관소우80 fs적초단맥충연추구전수시,연랍추방향,맥충불단전관,이당맥관대우80 fs시,맥충전관불명현.
Propagation constant and field evolution in the tapered region are discussed using numerical method based on waveguide theory.GNSE is resolved by the split-step Fourier method to study the transmission characteristics of ultra-short pulse in the tapered region.The calculated results show that at the beginning of the tapered fiber,propagation constant decreases gradually while in the end it drops dramatically.After the "transition point",energy redistributes in the fiber,and it becomes very large in the end.It is found that pulse width is broadened along the tapered region when the pulse width is smaller than 80fs.