Hou Yaping, Xu Yunfan, Du Bobo, Zhang Yanpeng, Zhang Lei
Opt Lett. 2024 Feb 1;49(3):470-473. doi: 10.1364/OL.511314.
Tuning polarization states of light electrically has unique advantages in the integration of optoelectronic devices. Here, a lithium niobate-based nanograting is proposed to dynamically tune the polarization state of both the reflected and transmitted lights simultaneously in the near-infrared range. By judiciously designing the nanograting, a quasi-bound state in the continuum (qBIC) is excited under the excitation of an obliquely incident plane wave. The excited mode with a high quality-factor and enhanced local electric field can respond to a refractive index change in nanograting structures as small as 10 level, which can be generated with a low external voltage via the electro-optic effect. As a result, both the polarization states of reflected and transmitted lights can be dynamically tuned from a right circular polarization to a linear polarization state. The proposed lithium niobate-based nanograting for tuning dual polarization states of light with a qBIC mode suggests a promising electrical scheme for achieving high speed optoelectronic devices.
通过电学方式调节光的偏振态在光电器件集成方面具有独特优势。在此，提出了一种基于铌酸锂的纳米光栅，用于在近红外范围内同时动态调节反射光和透射光的偏振态。通过精心设计纳米光栅，在倾斜入射平面波的激发下激发了一种连续谱中的准束缚态（qBIC）。具有高品质因数和增强局部电场的激发模式能够响应纳米光栅结构中低至10量级的折射率变化，这可以通过电光效应在低外部电压下产生。结果，反射光和透射光的偏振态都可以从右旋圆偏振动态调节为线偏振态。所提出的基于铌酸锂的用于通过qBIC模式调节光的双偏振态的纳米光栅为实现高速光电器件提供了一种有前景的电学方案。
