Du Bintao, Xia Jun, Wu Jun, Zhao Jian, Zhang Hao
Joint International Research Laboratory of Information Display and Visualization, School of Electronic Science and Engineering, Southeast University, Nanjing 210096, China.
Nanomaterials (Basel). 2019 Jan 6;9(1):72. doi: 10.3390/nano9010072.
This paper first presents a switchable photonic nanojet (PNJ) generated by a polystyrene (PS) microsphere immersed in nematic liquid crystals (NLCs). The PNJ is switched by applying external voltage, which originates from the refractive index change in the surrounding medium caused by the field-induced realignment of liquid crystal molecules. By tuning the refractive index of NLCs larger or smaller than that of the PS microsphere, the PNJ can be switched off or on. Moreover, we present an optimization study to seek a better electric energy focusing property of the PNJ. Our results reveal that the switchability of PNJ can be optimized by applying a shorter incident wavelength, a double-layer microsphere, and a PS ellipsoid. The full width at half-maximum (FWHM) generated by the PS ellipsoid is narrower than that generated by the microsphere with a shorter incident wavelength. The intensity contrast of the PS ellipsoid is higher than that of the double-layer microsphere. As a whole, the switchability of PNJ can be best optimized by a PS ellipsoid. This should open the way for the development of integrated photonic devices.
本文首先介绍了一种由浸没在向列型液晶（NLC）中的聚苯乙烯（PS）微球产生的可切换光子纳米射流（PNJ）。通过施加外部电压来切换PNJ，这源于由电场诱导的液晶分子重新排列所导致的周围介质折射率变化。通过将NLC的折射率调至大于或小于PS微球的折射率，PNJ可以被关闭或开启。此外，我们进行了一项优化研究，以寻求PNJ更好的电能聚焦特性。我们的结果表明，通过应用更短的入射波长、双层微球和PS椭球体，可以优化PNJ的可切换性。PS椭球体产生的半高全宽（FWHM）比具有更短入射波长的微球产生的半高全宽更窄。PS椭球体的强度对比度高于双层微球的强度对比度。总体而言，PS椭球体能够最佳地优化PNJ的可切换性。这应为集成光子器件的发展开辟道路。
Zotero 插件
