哈尔滨工业大学宋清海团队近日研究了具有任意形状波前的微纳激光器。2025年7月9日，《自然》杂志发表了这一成果。

集成纳米激光器已被探索了几十年，因为其在许多应用中发挥着重要作用，从光信息处理和通信到医疗。虽然纳米激光器的偏振、轨道角动量和指向性已被成功操纵，但它们的激光波前和辐射特性都不能被随意化。通常需要更多的光学元件来进一步修改激光特性，使激光系统体积庞大，并受到不可避免的散斑噪声的限制。

研究组提出并实现了一种新型激光器——微纳激光器，该激光器主要研究介电谐振超表面的局域和非局域响应之间的相互作用。激光模式受平面结构中元原子间非局域相互作用的限制，光束波前由局域变化的偶极动量精确地形成。因此，微纳激光器可以直接具有任何期望的轮廓，包括焦斑、焦线、矢量光束、涡旋光束甚至全息图。

值得注意的是，微纳激光器的散射波不像激光模式那样经历共振放大，弱几个数量级。因此，在其微纳激光全息图中，散斑噪声变得可以忽略不计，为传统激光全息图的散斑噪声问题提供了可行的解决方案。这一发现丰富了他们对激光器的理解，并促进了激光器在各种光学和光子应用中的性能。

附：英文原文

Title: Metalasers with arbitrarily shaped wavefront

Author: Zeng, Yixuan, Sha, Xinbo, Zhang, Chi, Zhang, Yao, Deng, Huachun, Lu, Haipeng, Qu, Geyang, Xiao, Shumin, Yu, Shaohua, Kivshar, Yuri, Song, Qinghai

Issue&Volume: 2025-07-09

Abstract: Integrated nanolasers have been explored for decades owing to their important role in many applications, ranging from optical information processing and communications to medical treatments1,2,3,4,5,6. Although polarization, orbital angular momentum and directivity of nanolasers have been successfully manipulated7,8,9, neither their laser wavefront nor radiation characteristics can be customized at will. More optical elements are often required to further modify the laser characteristics, making the lasing system bulky and restricted by inevitable speckle noise. Here we suggest and realize a new type of laser, a metalaser, by using the interplay between local and nonlocal responses of dielectric resonant metasurfaces. The lasing mode is confined by nonlocal interaction between meta-atoms of a planar structure and the beam wavefront is precisely shaped by locally varying dipole momenta. Consequently, the metalaser emission can directly have any desired profile, including focal spots, focal lines, vector beams, vortex beams and even holograms. Notably, the scattered waves of the metalaser do not undergo resonant amplification like laser modes, being orders of magnitude weaker. As a consequence, the speckle noise becomes negligibly small in our metalaser holograms, providing a viable solution to the speckle noise problem of conventional laser holograms. This finding enriches our understanding of lasers and promotes their performance for various optical and photonic applications.

DOI: 10.1038/s41586-025-09275-6

Source: https://www.nature.com/articles/s41586-025-09275-6