CAJ | 학술논문

利用时谐电磁场理论和时域有限差分数值方法分析了亚波长金属扫描探针电磁场模式的场型结构和空间分布及透射特性等主要的传输性质，导出了亚波长金属探针内球横电模和球横磁模各电磁场分量的解析表达，运用数值求解获得的精确本征值，得到了金属探针内几个低阶模在球横截面内的场型结构．时域有限差分数值模拟研究结果表明，时谐电磁场的空间分布在亚波长金属探针内呈现准周期性振荡变化，并且在传输径向坐标上会出现一个最大值，最大值的位置随光波波长发生改变，研究结果还表明，在亚波长探针内刻蚀可以更好地激发和引导表面等离子体激元波到达出射孔径端口，提高亚波长空心锥的透射率和增强光学仪器的空间分辨率．
이용시해전자장이론화시역유한차분수치방법분석료아파장금속소묘탐침전자장모식적장형결구화공간분포급투사특성등주요적전수성질，도출료아파장금속탐침내구횡전모화구횡자모각전자장분량적해석표체，운용수치구해획득적정학본정치，득도료금속탐침내궤개저계모재구횡절면내적장형결구．시역유한차분수치모의연구결과표명，시해전자장적공간분포재아파장금속탐침내정현준주기성진탕변화，병차재전수경향좌표상회출현일개최대치，최대치적위치수광파파장발생개변，연구결과환표명，재아파장탐침내각식가이경호지격발화인도표면등리자체격원파도체출사공경단구，제고아파장공심추적투사솔화증강광학의기적공간분변솔．
Based on the time-harmonic electromagnetic field theory and finite-difference time-domain （FDTD） method, the main propagation properties including the electromagnetic fields confignrations, the spatial distributions of field components and the transmission of a metallic scanning probe with a sub-wave- length-sized exit hole are analyzed. The analytical expressions for the field components of the spherical transverse-magnetic （TM） and transverse-electric （TE） modes inside the sub-wavelength metallic probe are derived. By using the accurate eigenvalues obtained numerically, some low order modal fields＇ config- urations are plotted. The numerical simulation results by FDTD show that the spatial distributions of time- harmonic electromagnetic field inside the probe vary quasi-periodically. The quasi-period has relation with the light wavelength, and there is a clearly pronounced maximum in the radial dependence. The position of an appreciable maximum for the time-averaged energy density varies rapidly with the light wavelength. It is also shown that corrugations inside the sub-wavelength probe can excite and guide the surface plasma polariton wave to exit hole better, which resulting in enhancing transmission of the sub-wavelength probe and spatial resolution of optical instrument.