We report the optical conductivity in high-quality crystals of the chiral topological semimetal CoSi, which hosts exotic quasiparticles known as multifold fermions. We find that the optical response is separated into several distinct regions as a function of frequency, each dominated by different types of quasiparticles. The low-frequency intraband response is captured by a narrow Drude peak from a high-mobility electron pocket of double Weyl quasiparticles, and the temperature dependence of the spectral weight is consistent with its Fermi velocity. By subtracting the low-frequency sharp Drude and phonon peaks at low temperatures, we reveal two intermediate quasilinear interband contributions separatedmore »
This content will become publicly available on December 1, 2022
- Publication Date:
- NSF-PAR ID:
- 10317813
- Journal Name:
- Atoms
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2218-2004
- Sponsoring Org:
- National Science Foundation
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