Author Affiliations
Abstract
1 Shandong Provincial Engineering and Technical Center of Light Manipulations & Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
2 School of Physical Science and Technology, Soochow University, Suzhou 215006, China
We investigated the Talbot effect in an anti-parity-time (PT) symmetric synthetic photonic lattice composed of two coupled fiber loops. We calculated the band structures and found that with an increase in the gain-loss parameter, the band transitions from a real spectrum to a complex spectrum. We study the influence of phase in the Hermitian operator on the Talbot effect, and the Talbot effect disappears when the period of the input field is N > 8. Further study shows that the variation of Talbot distance can also be modulated by non-Hermitian coefficients of gain and loss. This work may find significant applications in pulse repetition-rate multiplication, temporal invisibility, and tunable intensity amplifiers.
Talbot effect synthetic dimensions anti-PT symmetry photonic lattices Chinese Optics Letters
2024, 22(3): 031901
Author Affiliations
Abstract
1 Shandong Provincial Engineering and Technical Center of Light Manipulations & Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
2 School of Physical Science and Technology, Soochow University, Suzhou 215006, China
Self-healing in optics generally refers to the ability to reconstruct itself and restore the original state after encountering obstacles in the propagation of the light field. In this research, we observe the processes of the wave fields from perfect to defect in front of the focal plane of the 4f system, finally returning to an intact situation after the plane. According to simulations and experimental results, there is a minimum self-healing distance for the moiré lattice field that positively associates with the radius of the defect (obstacle) in the nondiffracting transmission range. Furthermore, it is observed that the defect self-healing is a process of “repairing the center and then repairing the edges.” These findings can be applied in areas such as optical imaging, capture, and information processing.
moiré lattice nondiffraction self-healing wave field Chinese Optics Letters
2023, 21(3): 030502
Author Affiliations
Abstract
1 State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-technology, Northwest University, Xi’an 710069, China
2 Shaanxi Engineering Technology Research Center for Solid State Lasers and Application, Provincial Key Laboratory of Photo-electronic Technology, Northwest University, Xi’an 710069, China
We reported a wavelength-flexible all-polarization-maintaining self-sweeping fiber laser based on the intracavity loss tuning brought by the bent optical fiber. The bidirectional cavity structure achieved the self-sweeping effect due to the appearance of the dynamic grating in the active fiber with the spatial hole burning effect. Under this, a section of fiber was bent into a circle for adjusting the loss of the cavity. With a descending diameter of bent fiber circle, the sweeping range moves to the shorter wavelength and covers a wide range from 1055.6 to 1034.6 nm eventually. Both the initial wavelength of self-sweeping regime and the threshold of the fiber laser show exponential correlation with the diameter of the circular fiber. Our work provides a compact and low-cost way to achieve the broad wavelength-flexible self-sweeping operation.
fiber laser self-sweeping effect bidirectional cavity flexible wavelength all-polarization maintaining Chinese Optics Letters
2021, 19(4): 041401
1 西北大学 物理学院, 西安 710069
2 西北大学 光子学与光子技术研究所/光电技术与功能材料省部共建国家重点实验室培育基地, 西安 710069
利用全息技术, 采用二元相位处理后的离散型艾里涡旋相位, 制作了一种双复合离散型艾里涡旋加速光.理论模拟和实验探究了该加速光的传输特性, 以及线性因子(s)、径向层数(N)和拓扑荷梯度(ΔL)对光场的调控机制.结果表明, 双加速光在传输过程中, 由于离散和旋转效应, 逐渐分离为多个类艾里光; 通过调节传输距离及ΔL, 可实现二维类艾里光至一维类艾里光之间的演化.此外, N和s可分别调节双加速光的强度分布及其在初始截面(z=0处的x-y平面)中的位置分布; ΔL也可调节分离的类艾里光之间的强度分布.
艾里涡旋光束 波传输 空间光调制器 全息技术 Airy vortex beam Wave propagation Spatial light modulator Holographic technique