近日，意大利国家研究委员会Istituto SPIN的Antonio Vecchione&Mario Cuoco及其研究团队取得一项新进展。经过不懈努力，他们揭示表面自旋轨道手性金属的特征。相关研究成果已于2024年2月7日在国际权威学术期刊《自然》上发表。

本文构建了对称破缺手性基态的理论框架，并提出了一种结合圆偏振、自旋选择以及角分辨光电子能谱的研究方法。研究人员运用这种方法对原型量子材料Sr₂RuO₄进行了深入研究，并揭示了其光谱特征。虽然这些特征相当微妙，但它们与材料表面自旋轨道手性电流的形成之间存在协调关系。通过对这些手性体系的深入研究，为理解有序现象和非常规磁性提供了新的视角和路径。

据悉，晶体对称性、电子关联性和电子结构之间的紧密联系催生了许多非传统物质相的形成，如磁电环电流和手性磁性等。这些隐性秩序的探索一直是凝聚态物理学领域的重要追求。然而，迄今为止，手性电子有序的非标准形式磁性在实验上的检测仍然面临极大的挑战。

附：英文原文

Title: Signatures of a surface spin–orbital chiral metal

Author: Mazzola, Federico, Brzezicki, Wojciech, Mercaldo, Maria Teresa, Guarino, Anita, Bigi, Chiara, Miwa, Jill A., De Fazio, Domenico, Crepaldi, Alberto, Fujii, Jun, Rossi, Giorgio, Orgiani, Pasquale, Chaluvadi, Sandeep Kumar, Chalil, Shyni Punathum, Panaccione, Giancarlo, Jana, Anupam, Polewczyk, Vincent, Vobornik, Ivana, Kim, Changyoung, Miletto-Granozio, Fabio, Fittipaldi, Rosalba, Ortix, Carmine, Cuoco, Mario, Vecchione, Antonio

Issue&Volume: 2024-02-07

Abstract: The relation between crystal symmetries, electron correlations and electronic structure steers the formation of a large array of unconventional phases of matter, including magneto-electric loop currents and chiral magnetism. The detection of such hidden orders is an important goal in condensed-matter physics. However, until now, non-standard forms of magnetism with chiral electronic ordering have been difficult to detect experimentally. Here we develop a theory for symmetry-broken chiral ground states and propose a methodology based on circularly polarized, spin-selective, angular-resolved photoelectron spectroscopy to study them. We use the archetypal quantum material Sr₂RuO₄ and reveal spectroscopic signatures that, despite being subtle, can be reconciled with the formation of spin–orbital chiral currents at the surface of the material. As we shed light on these chiral regimes, our findings pave the way for a deeper understanding of ordering phenomena and unconventional magnetism.

DOI: 10.1038/s41586-024-07033-8

Source: https://www.nature.com/articles/s41586-024-07033-8