• Nankai University Made Important Progress in Topological Photonics


    Nankai University’s Prof. Zhigang Chens and Prof. Jingjun Xu’s research groups have cooperated with University of Zagreb’s Prof. Hrvoje Buljan’s research group, making important progress in topological photonics. Through the experiment, they observed and theoretically proved that the topological charge conversion of pseudospin-orbit’s vortex is relevant to the topological characteristics of Dirac poles. The result of the experiment demonstrates a universal mapping of topological singularities from momentum to real space; it is published online with the name of “Universal momentum-to-real-space mapping of topological singularities” on the international authoritative journal “Nature Communications”.

    In recent years, in Condensed Matter Physics and Materials Physics, the material’s topological properties have become hot spots in academic studies. The team’s work not only provides a new perspective to understand topological physics, but also offers reference to the study on related topological phenomena in Condensed Matter Physics, Cold Atom Physics and other fields.

    Figures: (a) A pseudospin-1/2 honeycomb lattice with two sublattices A and B is excited with three vortex beams, each with topological charge l. (b) A pseudospin-1 Lieb lattice with three sites (A, B, C) per unit cell is excited with four vortex beams. (c) Illustration of similar excitation of a Berry curvature monopole in 3D momentum space, leading to generation of a topological charge in real space with vorticity along the direction of excitation.

    The paper’s first corresponding unit is Nankai University. Nankai University’s doctoral students Xiuying Liu and Shiqi Xia and University of Zagreb’s doctoral student Ema Jajtić are co-first authors. Nankai University’s Prof. Zhigang Chen, Vice Prof. Daohong Song and University of Zagreb’s Prof. Hrvoje Buljan are co-corresponding authors. This research is supported by the National Key R&D Program of China under Grant, the National Natural Science Foundation, and other projects.

    The research groups have already made series of important progress in pseudospin in Dirac cones and topological physics. Related works have been published on “Nature Materials”, “Nature Communications”, “Physical Review Letters” and other high-level journals.

    Link to the paper: https://rdcu.be/b3gD7

    (Reported by Daohong Song, Translated by Yuchen Shi,  Edited by Davide Francolino and JianjingYun)