January 20, 2021 | By Zhang Shunsheng | Copyedited by  Zhang Mingwei

     In 2020, the Future Optics Laboratory, led by Academician Zhuang Songlin and Academician Gu Min from University of Shanghai for Science and Technology, has made remarkable achievements in the field of photon orbital angular momentum research, drawing the attention of the international academic community. Meanwhile, the Nano-Optoelectronics Research Team, led by Professor Zhan Qiwen,  has had their research results published in Nature Photonics, a top academic journal in optics in the world, demonstrating for the first time from theory to experiment a new type of optical field of a spatiotemporal vortex phrase with a photon lateral orbital angular momentum, creating a completely new degree of freedom of photon orbital angular momentum (https://www.nature.com/articles/s41566-020-0587-z）. On that basis, Professor Zhan and his team members quickly carried out a series of work, realized the high-speed modulation to the photon orbital angular momentum in the time domain, and found an effective way to focus on the generation of highly localized transverse orbital angular momentum on the subwavelength space scale, further laying the groundwork for the further study of the interaction between this new photon state and matter. This series of research results has been selected by the Optical Society of America (OSA) as one of the World Top 30 Major Optical Achievements in 2020 (https://www.osa-opn.org/home/articles/volume_31/december_2020/features/optics_in_2020/).

       Using the Fourier transform from the spatial frequency–frequency domain to the spatial-temporal domain, the research team has successfully generated and represented the ultrashort pulse optical wave packet that carries transverse orbital angular momentum. While the photon energy is transmitted rapidly forward, the photon of the new wave packet can rotate around a transverse axis that moves along with the wave packet, therefore creating fast-moving photons similar to a hurricane. This discovery was recently selected by the China Laser Magazine as one of “the Top 10 News Events in China Optics” in 2020 (https://mp.weixin.qq.com/s/CZsOcQ7a-EIkUQj2bZHlEA).
        The progress on the research of photon lateral orbital angular momentum is a major breakthrough made by USST in the field of photon orbital angular momentum. The new dimension of photon orbital angular momentum discovered through the research provides potential research and application value in a wide range of areas such as optical communication, optical information processing, quantum optics, particle manipulation and relativistic space physics. Supported by the National Natural Science Foundation of China through a key project “Regulation Physics of a New Type of Light Field and Application of Major Research”, Zhan Qiwen will lead his group to make further systematic and in-depth research in this field, and look forward to extensive cooperation with academic counterparts from home and abroad.