CAJ | 학술논문

为了节省时域有限差分(FDTD)法的计算时间,提出了许多将FDTD的时域结果转换到频域的方法.文中介绍了一种基于Baker算法的Pade近似,并展示了其在光子晶体模拟中的应用.对频率为160THz,品质因子为5000的简单谐振子,结果显示Padé近似用28时间步数据得到的强度谱比快速傅里叶变换用220时间步数据得到的强度谱更精确.采用这一Padé近似,光子晶体平板结构中不同波矢对应的模式频率和品质因子及其能带结构可以在很短的FDTD输出结果下得出.另外,Padé近似也用于计算光子晶体微腔的模式频率和品质因子.
위료절성시역유한차분(FDTD)법적계산시간,제출료허다장FDTD적시역결과전환도빈역적방법.문중개소료일충기우Baker산법적Pade근사,병전시료기재광자정체모의중적응용.대빈솔위160THz,품질인자위5000적간단해진자,결과현시Padé근사용28시간보수거득도적강도보비쾌속부리협변환용220시간보수거득도적강도보경정학.채용저일Padé근사,광자정체평판결구중불동파시대응적모식빈솔화품질인자급기능대결구가이재흔단적FDTD수출결과하득출.령외,Padé근사야용우계산광자정체미강적모식빈솔화품질인자.
To save finite-difference time-domain(FDTD) computing time, several methods are proposed to convert the time domain FDTD output into frequency domain. The Padé approximation with Baker's algorithm and the program are introduced to simulate photonic crystal structures. For a simple pole system with frequency 160THz and quality factor of 5000,the intensity spectrum obtained by the Padé approximation from a 28-item sequence output is more exact than that obtained by fast Fourier transformation from a 220-item sequence output. The mode frequencies and quality factors are calculated at different wave vectors for the photonic crystal slab from a much shorter FDTD output than that required by the FFT method,and then the band diagrams are obatined. In addition,mode frequencies and Q-factors are calculated for photonic crystal microcavity.