熔融拉制微纳光纤耦合器的仿真模拟

摘要

为了对微纳光纤耦合器进行研究,采用光束传播法,在不同熔融区长度和不同波长输入光情况下对微纳光纤耦合器的熔融拉制过程进行数值模拟,取得了输出光功率随拉伸长度变化的曲线和光场分布,并分析了耦合器的3个阶段的模场变化和光场特点.结果表明,当拉伸到微纳光纤耦合器失去有效耦合阶段时,两光纤的输出光功率趋于相等且不再随拉伸长度的变化而变化;熔融拉锥耦合器在各个阶段的光场分布特点不同;熔锥型的微纳光纤耦合器失去有效耦合与熔融区的光纤直径直接关联,且此光纤直径与输入光的波长有关,波长越小,熔融区需经拉伸达到的光纤直径越小.这一结果对研究微纳光纤耦合器失去有效耦合的成立条件是有帮助的.%In order to study micronano fiber couplers,numerical simulation of the melting and drawing process of micronano fiber couplers was carried out by using beam propagation method.The curves of output light power with the change of tensile length and the distribution diagram of light field were obtained.The change of mode field and the characteristics of light field of three phases of the coupler were analyzed through software simulation.The results show that output light power of two fibers tends to be equal and no longer varies with the change of tensile length when a micronano fiber coupler is in the phase of losing the effective coupling.The characteristics of light field distribution of the fused taper coupler at various stages are different.The loss of effective coupling of taper-type micronano fiber coupler is directly related to fiber diameter of the melting zone.And the fiber diameter is related to the input light wavelength.The smaller the wavelength is,the smaller the fiber diameter that should be reached by the melt zone is.It is helpful for the study of the conditions for the loss of effective coupling of micronano fiber coupler.