Weyl spin-momentum locking in a chiral topological semimetal
(2024) In Nature Communications 15(1).- Abstract
Spin-orbit coupling in noncentrosymmetric crystals leads to spin-momentum locking – a directional relationship between an electron’s spin angular momentum and its linear momentum. Isotropic orthogonal Rashba spin-momentum locking has been studied for decades, while its counterpart, isotropic parallel Weyl spin-momentum locking has remained elusive in experiments. Theory predicts that Weyl spin-momentum locking can only be realized in structurally chiral cubic crystals in the vicinity of Kramers-Weyl or multifold fermions. Here, we use spin- and angle-resolved photoemission spectroscopy to evidence Weyl spin-momentum locking of multifold fermions in the chiral topological semimetal PtGa. We find that the electron spin of the Fermi arc... (More)
Spin-orbit coupling in noncentrosymmetric crystals leads to spin-momentum locking – a directional relationship between an electron’s spin angular momentum and its linear momentum. Isotropic orthogonal Rashba spin-momentum locking has been studied for decades, while its counterpart, isotropic parallel Weyl spin-momentum locking has remained elusive in experiments. Theory predicts that Weyl spin-momentum locking can only be realized in structurally chiral cubic crystals in the vicinity of Kramers-Weyl or multifold fermions. Here, we use spin- and angle-resolved photoemission spectroscopy to evidence Weyl spin-momentum locking of multifold fermions in the chiral topological semimetal PtGa. We find that the electron spin of the Fermi arc surface states is orthogonal to their Fermi surface contour for momenta close to the projection of the bulk multifold fermion at the Γ point, which is consistent with Weyl spin-momentum locking of the latter. The direct measurement of the bulk spin texture of the multifold fermion at the R point also displays Weyl spin-momentum locking. The discovery of Weyl spin-momentum locking may lead to energy-efficient memory devices and Josephson diodes based on chiral topological semimetals.
(Less)
- author
- organization
- publishing date
- 2024-12
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Nature Communications
- volume
- 15
- issue
- 1
- article number
- 3720
- publisher
- Nature Publishing Group
- external identifiers
-
- pmid:38697958
- scopus:85192001122
- ISSN
- 2041-1723
- DOI
- 10.1038/s41467-024-47976-0
- language
- English
- LU publication?
- yes
- id
- a95daeb4-91d7-4e1c-a6ae-b024cf136b1b
- date added to LUP
- 2024-05-16 13:07:44
- date last changed
- 2024-05-30 14:59:18
@article{a95daeb4-91d7-4e1c-a6ae-b024cf136b1b, abstract = {{<p>Spin-orbit coupling in noncentrosymmetric crystals leads to spin-momentum locking – a directional relationship between an electron’s spin angular momentum and its linear momentum. Isotropic orthogonal Rashba spin-momentum locking has been studied for decades, while its counterpart, isotropic parallel Weyl spin-momentum locking has remained elusive in experiments. Theory predicts that Weyl spin-momentum locking can only be realized in structurally chiral cubic crystals in the vicinity of Kramers-Weyl or multifold fermions. Here, we use spin- and angle-resolved photoemission spectroscopy to evidence Weyl spin-momentum locking of multifold fermions in the chiral topological semimetal PtGa. We find that the electron spin of the Fermi arc surface states is orthogonal to their Fermi surface contour for momenta close to the projection of the bulk multifold fermion at the Γ point, which is consistent with Weyl spin-momentum locking of the latter. The direct measurement of the bulk spin texture of the multifold fermion at the R point also displays Weyl spin-momentum locking. The discovery of Weyl spin-momentum locking may lead to energy-efficient memory devices and Josephson diodes based on chiral topological semimetals.</p>}}, author = {{Krieger, Jonas A. and Stolz, Samuel and Robredo, Iñigo and Manna, Kaustuv and McFarlane, Emily C. and Date, Mihir and Pal, Banabir and Yang, Jiabao and B. Guedes, Eduardo and Dil, J. Hugo and Polley, Craig M. and Leandersson, Mats and Shekhar, Chandra and Borrmann, Horst and Yang, Qun and Lin, Mao and Strocov, Vladimir N. and Caputo, Marco and Watson, Matthew D. and Kim, Timur K. and Cacho, Cephise and Mazzola, Federico and Fujii, Jun and Vobornik, Ivana and Parkin, Stuart S.P. and Bradlyn, Barry and Felser, Claudia and Vergniory, Maia G. and Schröter, Niels B.M.}}, issn = {{2041-1723}}, language = {{eng}}, number = {{1}}, publisher = {{Nature Publishing Group}}, series = {{Nature Communications}}, title = {{Weyl spin-momentum locking in a chiral topological semimetal}}, url = {{http://dx.doi.org/10.1038/s41467-024-47976-0}}, doi = {{10.1038/s41467-024-47976-0}}, volume = {{15}}, year = {{2024}}, }