薄膜微盘激射性质  

Directional emission properties of thin film microdisk

作　　者：徐宇轩 姚泰宇 邓莉[1] 陈诗枚 徐辰尧 唐文轩 Xu Yu-Xuan;Yao Tai-Yu;Deng Li;Chen Shi-Mei;Xu Chen-Yao;Tang Wen-Xuan(School of Physics and Electronic Science,East China Normal University,Shanghai 200241,China)

机构地区：[1]华东师范大学物理与电子科学学院,上海200241

出　　处：《物理学报》2024年第8期105-114,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12174113)资助的课题.

摘　　要：基于半导体变形微腔的定向激射效应,在各向同性薄膜中制备变形微腔,将为多功能、高集成光子有源芯片提供新的解决方案.利用二维波动光学理论,以Z切向掺饵铌酸锂薄膜蚶线形微盘中的TE20,1模式为例,分析了不同变形因子ε微盘的模式分布、品质因子Q、定向激射效果D以及庞加莱截面图.理论模拟结果显示,微盘变形过程中微盘周长与谐振波长的比值近似为一定值.当ε大于0.24时,微盘具有较好的单向激射性,Q值大于10^(5);当ε变形因子大于0.4时,庞加莱截面图几乎被混沌海区域占据,Q值低于10^(3).因此,薄膜蚶线形微盘变形因子ε在0.24—0.4之间时,微盘不仅具有高的品质因子(Q值为10^(3)—10^(5)),激射方向性也较高(D值为6.45—8.32).Based on the directional emission effect of semiconductor deformed microcavities,the fabrication of deformed micro cavities in isotropic thin films will provide a new solution for multifunctional and highly integrated photonic active chips.Because the Limacon shaped microcavity has become one of the important configurations of single-mode,low threshold on-chip lasers,the directional emission properties of microdisks fabricated in thin film are investigated.Taking the TE_(20,1)mode existing in the Z-cut lithium niobate thin film microdisk for example,according to two-dimensional wave optics theory,the mode distribution,quality factor Q,and directional emission factor D of microdisk variations with deformation factorεare respectively analyzed through using the wave optics module of COM SOL.Adopting classical scattering theory,Poincare surfaces of sections under different deformation factors are simulated by optimizing the Dynamical Billards.jl library in Julia.In the simulation realized by Julia,200 particle collisions are used 200 times to simulate 200 reflections of rays and finally PSOS images are obtained.Simulation results reveal that when the azimuthal quantum number of the light wave mode remains unchanged,although the shape of the microdisk varies,the ratio of the resonant wavelength inside the microdisk to the circumference of the microdisk is approximately a constant,which can predict the microdisk size and resonant wavelength estimation of microcavities.The corresponding PSOS shows that when ε>0.45,the entire region is covered by chaotic sea area,thereforeεvalues of 0,0.16,0.24,0.28,0.45 are selected to simulate the TE_(20,1)mode distribution,far-field radiation flux angle distribution,and PSOS.Theoretical simulation results show that when the deformation factor is greater than 0.24,the microdisk has good unidirectional lasing property,with a Q factor greater than 10^(5).When the deformation factor is greater than 0.4,the PSOS is almost occupied by the chaotic sea area,with a Q factor below 10^(3).The

关 键 词：蚶线形微盘 模式分布 品质因子 定向激射 

分 类 号：O484.4[理学—固体物理]