Author Affiliations
Abstract
1 Nanyang Technological University, School of Electrical and Electronic Engineering, Singapore
2 Shanghai Jiao Tong University, School of Electronic Information and Electrical Engineering, Shanghai, China
3 Chinese Academy of Sciences, Shanghai Institute of Microsystem and Information Technology, State Key Laboratory of Transducer Technology, Shanghai, China
4 Taiwan Chung Cheng University, Department of Mechanical Engineering, Minhsiung, Chiayi, China
5 Nanyang Technological University, School of Chemical and Biomedical Engineering, Singapore
Liquid droplets offer a great number of opportunities in biochemical and physical research studies in which droplet-based microlasers have come into play over the past decade. While the recent emergence of droplet lasers has demonstrated their powerful capabilities in amplifying subtle molecular changes inside the cavity, the optical interactions between droplet resonators and an interface remain unclear. We revealed the underlying mechanism of droplet lasers when interacting with a droplet–solid interface and explored its correlation with intermolecular forces. A vertically oriented oscillation mode—arc-like mode—was discovered, where the number of lasing modes and their Q-factors increase with the strength of interfacial hydrophobicity. Both experimental and theoretical results demonstrated that hydrophobicity characterized by contact angle and interfacial tension plays a significant role in the geometry of droplet cavity and laser mode characteristics. Finally, we demonstrated how tiny forces induced by proteins and peptides could strongly modulate the lasing output in droplet resonators. Our findings illustrate the potential of exploiting optical resonators to amplify intermolecular force changes, providing comprehensive insights into lasing actions modulated by interfaces and applications in biophysics.
microlaser droplet resonator intermolecular forces biointerface lasing action hydrophobicity Advanced Photonics
2021, 3(1): 016003
Author Affiliations
Abstract
1 School of Physics and Astronomy, Key Laboratory for Laser Plasmas (Ministry of Education), Collaborative Innovation center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
2 Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
3 SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
Optical vortex is a promising candidate for capacity scaling in next-generation optical communications. The generation of multi-vortex beams is of great importance for vortex-based optical communications. Traditional approaches for generating multi-vortex beams are passive, unscalable and cumbersome. Here, we propose and demonstrate a multi-vortex laser, an active approach for creating multi-vortex beams directly at the source. By printing a specially-designed concentric-rings pattern on the cavity mirror, multi-vortex beams are generated directly from the laser. Spatially, the generated multi-vortex beams are decomposable and coaxial. Temporally, the multi-vortex beams can be simultaneously self-mode-locked, and each vortex component carries pulses with GHz-level repetition rate. Utilizing these distinct spatial-temporal characteristics, we demonstrate that the multi-vortex laser can be spatially and temporally encoded for data transmission, showing the potential of the developed multi-vortex laser in optical communications. The demonstrations may open up new perspectives for diverse applications enabled by the multi-vortex laser.
Author Affiliations
Abstract
1 Key Laboratory for Laser Plasmas of the Ministry of Education, Collaborative Innovation Center of IFSA (CICIFSA), School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
2 Key Laboratory of Materials for High Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
High-power ultrafast fiber lasers operating at the 2 μm wavelength are extremely desirable for material processing, laser surgery, and nonlinear optics. Here we fabricated large-core (LC) double-cladding Tm-doped silica fiber via the sol-gel method. The sol-gel-fabricated Tm-doped silica (SGTS) fiber had a large core diameter of 30 μm with a high refractive index homogeneity (Δn=2×10 4). With the newly developed LC SGTS fiber as the gain fiber, high-power mode-locking was realized. By using a semiconductor saturable absorber mirror (SESAM) as a mode locker, the LC SGTS fiber oscillator generated mode-locked pulses with an average output power as high as 1.0 W and a pulse duration of 23.9 ps at the wavelength of 1955.0 nm. Our research results show that the self-developed LC Tm-doped silica fiber via the sol-gel method is a promising gain fiber for generating high-power ultrafast lasers in the 2 μm spectral region.
060.2290 Fiber materials 060.3510 Lasers, fiber 140.4050 Mode-locked lasers Chinese Optics Letters
2018, 16(2): 020020
针对二维数字散斑斜光轴近距离测量时由于镜头光轴和待测目标面不垂直引起的误差问题，根据光学原理推导出不同角度拍摄时修正镜头畸变的校准应变公式。通过标准试件在弹性范围内进行拉压实验，验证校准应变公式对数字散斑图像测量数据修正的有效性，并与理论计算和应变片测试值进行比较。结果表明修正后的应变值误差在9.24%之内，提高了二维数字散斑相关测量技术的效率和精度。
成像系统 数字散斑相关技术 镜头畸变 误差修正 应变 激光与光电子学进展
2015, 52(5): 051101
