Azimuthally and radially polarized orbital angular momentum modes in valley topological photonic crystal fiber
Zhang Zhishen,
Lu Jiuyang,
Liu Tao,
Gan Jiulin,
Heng Xiaobo,
Wu Minbo,
Li Feng,
Yang Zhongmin
Affiliations
Zhang Zhishen
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Lu Jiuyang
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Liu Tao
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Gan Jiulin
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Heng Xiaobo
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Wu Minbo
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Li Feng
Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing100081, China
Yang Zhongmin
School of Physics and Optoelectronic Technology, South China University of Technology,Guangzhou, Guangdong510640, China
Artificially tailoring the polarization and phase of light offers new applications in optical communication, optical tweezers, and laser processing. Valley topological physics provides a novel paradigm for controlling electromagnetic waves and encoding information. The proposed fiber has the inner and outer claddings possessing opposite valley topological phases but the same refractive indices, which breaks through the polarization constraints of the traditional fiber. Robust valley edge states exist at the domain walls between the inner and outer claddings because of bulk edge correspondence. The valley topological fiber modes exhibit the unprecedented radial and azimuthal polarization with high-order azimuthal index. Those topological modes are robust against the disorder of the fiber structure. These results enable guide and manipulate the optical polarization and angular momentum in fiber with high fidelity. The proposed fiber has the potential to become a powerful optical spanner for the application of bio-photonics.
