Kramers-Weyl fermions in the chiral charge density wave material (TaSe$_4$)$_2$I

التفاصيل البيبلوغرافية
العنوان: Kramers-Weyl fermions in the chiral charge density wave material (TaSe$_4$)$_2$I
المؤلفون: Kim, Soyeun, McKay, Robert C., Bielinski, Nina, Zhao, Chengxi, Lin, Meng-Kai, Hlevyack, Joseph A., Guo, Xuefei, Mo, Sung-Kwan, Abbamonte, Peter, Chiang, Tai-Chang, Schleife, André, Shoemaker, Daniel P., Bradlyn, Barry, Mahmood, Fahad
سنة النشر: 2021
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Mesoscale and Nanoscale Physics
الوصف: The quasi-one-dimensional chiral charge density wave (CDW) material (TaSe$_4$)$_2$I has been recently predicted to host Kramers-Weyl (KW) fermions which should exist in the vicinity of high symmetry points in the Brillouin zone in chiral materials with strong spin-orbit coupling. However, direct spectroscopic evidence of KW fermions is limited. Here we use helicity-dependent laser-based angle resolved photoemission spectroscopy (ARPES) in conjunction with tight-binding and first-principles calculations to identify KW fermions in (TaSe$_4$)$_2$I. We find that topological and symmetry considerations place distinct constraints on the (pseudo-) spin texture and the observed spectra around a KW node. We further reveal an interplay between the spin texture around the chiral KW node and the onset of CDW order in (TaSe$_4$)$_2$I. Our findings highlight the unique topological nature of (TaSe$_4$)$_2$I and provide a pathway for identifying KW fermions in other chiral materials.
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2108.10874
رقم الأكسشن: edsarx.2108.10874
قاعدة البيانات: arXiv