Zhu Wenguo, Yu Jianhui, Guan Heyuan, Lu Huihui, Tang Jieyuan, Zhang Jun, Luo Yunhan, Chen Zhe
Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Jinan University, Guangzhou, 510632, China.
Department of Optoelectronic Engineering, Jinan University, Guangzhou, 510632, China.
Sci Rep. 2017 Apr 25;7(1):1150. doi: 10.1038/s41598-017-01323-0.
Optical spin splitting has a promising prospect in quantum information and precision metrology. Since it is typically small, many efforts have been devoted to its enhancement. However, the upper limit of optical spin splitting remains uninvestigated. Here, we investigate systematically the in-plane spin splitting of a Gaussian beam reflected from a glass-air interface and find that the spin splitting can be enhanced in three different incident angular ranges: around the Brewster angle, slightly smaller than and larger than the critical angle for total reflection. Within the first angular range, the reflected beam can undergo giant spin splitting but suffers from low energy reflectivity. In the second range, however, a large spin splitting and high energy reflectivity can be achieved simultaneously. The spin splitting becomes asymmetrical within the last angular range, and the displacement of one spin component can be up to half of incident beam waist w /2. Of all the incident angles, the spin splitting reaches its maximum at Brewster angle. This maximum splitting increases with the refractive index of the "glass" prism, eventually approaching an upper limit of w . These findings provide a deeper insight into the optical spin splitting phenomena and thereby facilitate the development of spin-based applications.
光学自旋分裂在量子信息和精密计量学方面有着广阔的前景。由于其通常较小，人们已付出诸多努力来增强它。然而，光学自旋分裂的上限仍未得到研究。在此，我们系统地研究了从玻璃 - 空气界面反射的高斯光束的面内自旋分裂，发现自旋分裂可在三个不同的入射角度范围内增强：在布儒斯特角附近、略小于和大于全反射临界角。在第一个角度范围内，反射光束可经历巨大的自旋分裂，但能量反射率较低。然而，在第二个范围内，可同时实现大的自旋分裂和高能量反射率。在最后一个角度范围内，自旋分裂变得不对称，一个自旋分量的位移可达入射光束腰宽(w)的一半。在所有入射角中，自旋分裂在布儒斯特角处达到最大值。这个最大分裂随着“玻璃”棱镜的折射率增加，最终接近(w)的上限。这些发现为光学自旋分裂现象提供了更深入的见解，从而推动基于自旋的应用发展。
