Programmable complex pumping field induced color-on-demand random lasing in fiber-integrated microbelts for speckle free imaging  

作　　者：Xiaoyu SHI Kaiyue SHEN Yaoxing BIAN Wanting SONG Jun RUAN Zhaona WANG Tianrui ZHAI 

机构地区：[1]College of Physics and Optoelectronics,Faculty of Science,Beijing University of Technology,Beijing 100124,China [2]Applied Optics Beijing Area Major Laboratory,Department of Physics,Beijing Normal University,Beijing 100875,China

出　　处：《Science China(Information Sciences)》2023年第12期247-256,共10页中国科学（信息科学）（英文版）

摘　　要：Miniaturized lasers with on-demand color emission have immense potential in the development of integrated imaging sources. Random lasers(RLs) with cavity-free structures and low spatial coherence are promising candidates for multicolor imaging sources. However, the wide tuning range and high tuning accuracy of continuous and reversible random lasing color with a defined emissive direction remain challenging. Here, random lasing with on-demand color emission and defined emissive direction is realized in fiber-integrated microbelts through programmable pumping. Individual RL microbelts as RL units doped with blue(B)-, green(G)-, and red(R)-emissive dyes and titanium dioxide nanoparticles are assembled on an optical fiber, resulting in high-performance B/G/R lasing. The optical fiber functions as a waveguide that guides the multicolor RL to ensure a defined directional emission. By manipulating the combination of the B/G/R RL units on the waveguide, distinctive lasing colors covering the entire visible spectrum are obtained, including white-colored random lasing. To realize dynamically controllable lasing for on-demand color emission, a pumping strategy with programmable excitation is proposed by shaping the pump beams into different beam arrays for precisely pumping the RL unit combination. We envision that fiber-integrated RL sources can be implemented in various imaging applications, such as biomedical diagnosis, multiplexed communication, and optical sensing.

关 键 词：random laser multi-color pump control fiber-integrated directional emission 

分 类 号：TN248[电子电信—物理电子学]