Understanding the intimate nature of unconventional electronic and magnetic orders and providing robust means for detecting them are key objectives in the field of condensed-matter physics. For instance, identifying non-standard types of magnetism with chiral electronic ordering has proven to be quite challenging. Here, we introduce and discuss symmetry-broken chiral phases which are based on nonstandard orbital and spin-orbital quadrupole currents [1]. We discuss the magnetic character of these phases and their properties [1,2]. Then, we consider which are the key signatures for their detection when considering circularly polarized, spin-selective, angular-resolved photoelectron spectroscopy. Focusing on the well-known quantum material Sr₂RuO₄, we uncover spectroscopic hallmarks that align with the presence of spin-orbital chiral currents at the material's surface [1]. Hence, we present another remarkable phenomenon associated with multipolar loop currents: spin handedness-selective signals that surpass conventional dichroic, spin, and spin-dichroic responses [3]. We observe this phenomenon in the kagome metal CsTi₃Bi₅ and we call it the anomalous spin-optical helical effect. This effect arises from the interplay of light' s helicity with spin-orbital electron correlations, providing a groundbreaking method to visualize multipolar loop currents in quantum materials. These findings not only enrich the debate surrounding loop currents but also paves the way for new strategies to exploit the electronic phases of quantum materials via light-matter interaction. [1] F. Mazzola, W. Brzezicki, M. T. Mercaldo,…, M. Cuoco, A. Vecchione, “Signatures of a surface spin-orbital chiral metal”, Nature 626, 752–758 (2024). [2] R. Fittipaldi, R. Hartmann, M. T. Mercaldo, ..., M. Cuoco, Z. Salman, A. Vecchione, A. Di Bernardo, "Unveiling unconventional magnetism at the surface of Sr₂RuO₄", Nature Communications 12, 5792 (2021). [3] F. Mazzola, W. Brzezicki, C. Bigi, …, C. Ortix, M. Cuoco, “Anomalous spin-optical helical effect in Ti-based kagome metal”, arXiv:2502.19589 (2025). We acknowledge support by Italian Ministry of University and Research (MUR) PRIN 2022 under the Grant No. 2022LP5K7 (BEAT) and from PNRR MUR Project No. PE0000023-NQSTI.

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