Weyl, Dirac and high-fold chiral fermions in topological quantum materials.
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TLDR
A review of Weyl-line phases in magnetic topological materials can be found in this article, where the authors provide an introduction to the basic concepts underlying Weyl physics in condensed matter and to representative materials and their electronic structures and topology as revealed by spectroscopic studies.Abstract:
Quantum materials hosting Weyl fermions have opened a new era of research in condensed matter physics. First proposed in 1929 in particle physics, Weyl fermions have yet to be observed as elementary particles. In 2015, Weyl fermions were detected as collective electronic excitations in the strong spin-orbit coupled material tantalum arsenide, TaAs. This discovery was followed by a flurry of experimental and theoretical explorations of Weyl phenomena in materials. Weyl materials naturally lend themselves to the exploration of the topological index associated with Weyl fermions and their divergent Berry curvature field, as well as the topological bulk-boundary correspondence giving rise to protected conducting surface states. Here, we review the broader class of Weyl topological phenomena in materials, starting with the observation of emergent Weyl fermions in the bulk and of Fermi arc states on the surface of the TaAs family of crystals by photoemission spectroscopy. We then discuss some of the exotic optical and magnetic responses observed in these materials, as well as the progress in developing some of the related chiral materials. We discuss the conceptual development of high-fold chiral fermions, which generalize Weyl fermions, and we review the observation of high-fold chiral fermion phases by taking the rhodium silicide, RhSi, family of crystals as a prime example. Lastly, we discuss recent advances in Weyl-line phases in magnetic topological materials. With this Review, we aim to provide an introduction to the basic concepts underlying Weyl physics in condensed matter, and to representative materials and their electronic structures and topology as revealed by spectroscopic studies. We hope this work serves as a guide for future theoretical and experimental explorations of chiral fermions and related topological quantum systems with potentially enhanced functionalities.read more
Citations
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References
More filters
Journal ArticleDOI
Large anomalous Hall current induced by topological nodal lines in a ferromagnetic van der Waals semimetal.
Kyoo Kim,Junho Seo,Eunwoo Lee,Kyung-Tae Ko,Byung-Ho Kim,Bo Gyu Jang,Jong Mok Ok,Jinwon Lee,Younjung Jo,Woun Kang,Ji Hoon Shim,Changyoung Kim,Han Woong Yeom,Byung Il Min,Bohm-Jung Yang,Jun Sung Kim +15 more
TL;DR: A combined experimental and theoretical approach identifies the van der Waals material Fe3GeTe2 as a candidate ferromagnetic nodal line semimetal and extends the connections between topology and magnetism.
Journal ArticleDOI
Spectroscopic evidence for type II Weyl semimetal state in MoTe2
Lunan Huang,Timothy M. McCormick,Masayuki Ochi,Zhiying Zhao,Michi-To Suzuki,Ryotaro Arita,Yun Wu,Daixiang Mou,Huibo Cao,Jiaqiang Yan,Nandini Trivedi,Adam Kaminski +11 more
TL;DR: In this article, a type II topological Weyl semimetal (TWS) was discovered in pure MoTe2, where two sets of WPs (W2+-, W3+-) exist at the touching points of electron and hole pockets and are located at different binding energies above Ef.
Journal ArticleDOI
Observation of three-component fermions in the topological semimetal molybdenum phosphide
B. Q. Lv,Zili Feng,Qiunan Xu,Xiang Gao,Junzhang Ma,Lingyuan Kong,Pierre Richard,Yaobo Huang,Vladimir N. Strocov,Chen Fang,Hongming Weng,Youguo Shi,Tianmei Qian,Hong Ding +13 more
TL;DR: An angle-resolved photoemission spectroscopy is used to demonstrate the existence of a triply degenerate point in the electronic structure of crystalline molybdenum phosphide, which opens up a way of exploring the new physics of unconventional fermions in condensed-matter systems.
Journal ArticleDOI
Observation of Topological Nodal Fermion Semimetal Phase in ZrSiS
Madhab Neupane,Ilya Belopolski,M. Mofazzel Hosen,Daniel S. Sanchez,Raman Sankar,Maria Szlawska,Su-Yang Xu,Klauss Dimitri,Nagendra Dhakal,Pablo Maldonado,Peter M. Oppeneer,Dariusz Kaczorowski,Fangcheng Chou,M. Zahid Hasan,Tomasz Durakiewicz +14 more
TL;DR: In this article, the spinless nodal fermion semimetal phase in ZrSiS was established using angle-resolved photoemission spectroscopy and first-principles calculations.
Journal ArticleDOI
Direct optical detection of Weyl fermion chirality in a topological semimetal
Qiong Ma,Su-Yang Xu,Ching-Kit Chan,Ching-Kit Chan,Chenglong Zhang,Guoqing Chang,Yuxuan Lin,Weiwei Xie,Tomas Palacios,Hsin Lin,Shuang Jia,Patrick A. Lee,Pablo Jarillo-Herrero,Nuh Gedik +13 more
TL;DR: Measuring the photocurrent response to circularly polarized mid-infrared light provides direct access to the chirality of Weyl fermions in Weyl semimetals.