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antiferromagnetism, X-ray circular dichroism, soft X-ray scattering
NSRRC Distinguished Scientist Di-Jing Huang's Collaborative Research on Antiferromagnetism Featured on the Back Cover of Advanced Materials
2024/06/28
The latest achievement of Prof. Di-Jing Huang's team is featured on the back cover of Advanced Materials. The image illustrates the unique feature of altermagnetism of chrial material Ni3TeO6.
An international collaborative research team consisting of scientists from the NSRRC, Department of Physics at National Tsing Hua University (NTHU), and Rutgers University in the USA has discovered a novel magnetic material with a net magnetic moment and giant circular dichroism, revolutionizing the traditional concepts of magnetic materials. This groundbreaking research was led by Prof. Di-Jing Huang, NSRRC Distinguished Scientist and Adjunct Professor at NTHU; Prof. Atsushi Fujimori, NSRRC Distinguished Visiting Scholar and NTHU Yushan Fellow; and Prof. Chung-Yu Mou of NTHU. It was published in the prominent international journal Advanced Materials on June 20 and featured on the back cover of the current issue (volume 36, issue 25).

The first author of the research paper is Dr. Jun Okamoto of the NSRRC, with major co-authors Dr. Hung-Wei Shiu, Dr. Amol Singh, Dr. Hsiao-Yu Huang, and Dr. Chien-Te Chen from the NSRRC, as well as Prof. Sang-Wook Cheong from Rutgers University. The team redefines the conventional understanding of magnetic materials by demonstrating that the new magnetic material, Ni3TeO6, does not have a net magnetic moment but exhibits giant natural circular dichroism. The helical structure is commonly found in materials; it can be either left-handed or right-handed, which absorbs left-handed and right-handed circularly polarized light differently. Circular dichroism refers to the difference in the absorption of circularly polarized light depending on the direction of a material's net magnetic moment. If a material has zero net magnetic moment, it typically has the same absorption rate for both left-handed and right-handed circularly polarized light. However, the novel material Ni3TeO6 shows a significant difference in the absorption of left-handed and right-handed circularly polarized light despite having no net magnetic moment. This finding defies conventional understanding and proposes the pioneering instance of this new type of magnetic material. The study provides new evidence for the interaction between spins and chiral crystal structures in natural optical activity and, for the first time, establishes a new class of antiferromagnetic materials that maintain time-reversal symmetry while exhibiting circular dichroism.