Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene
We identify and describe how intense short light pulses couple to massless Dirac fermions in two-dimensional systems. The ensuing excitation dynamics exhibits unusual scaling with the wavelength of the light due the linear dispersion of the band structure and the fact that light coupling is efficien...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2022-04-01
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| Series: | Physical Review Research |
| Online Access: | http://doi.org/10.1103/PhysRevResearch.4.L022014 |
| _version_ | 1797210791100809216 |
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| author | Hamed Koochaki Kelardeh Ulf Saalmann Jan M. Rost |
| author_facet | Hamed Koochaki Kelardeh Ulf Saalmann Jan M. Rost |
| author_sort | Hamed Koochaki Kelardeh |
| collection | DOAJ |
| description | We identify and describe how intense short light pulses couple to massless Dirac fermions in two-dimensional systems. The ensuing excitation dynamics exhibits unusual scaling with the wavelength of the light due the linear dispersion of the band structure and the fact that light coupling is efficient only close to the Dirac points. We exploit these features to achieve valley polarization of more than 70% with simple pulse shapes. Thereby, we demonstrate that substantial valley polarization at moderate excitation can be achieved with a suitable linearly polarized pulse in gapless systems. Quantitative results are given for pristine graphene. |
| first_indexed | 2024-04-24T10:16:12Z |
| format | Article |
| id | doaj.art-63c4982f7a1845f489d6d3aae4506129 |
| institution | Directory Open Access Journal |
| issn | 2643-1564 |
| language | English |
| last_indexed | 2024-04-24T10:16:12Z |
| publishDate | 2022-04-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review Research |
| spelling | doaj.art-63c4982f7a1845f489d6d3aae45061292024-04-12T17:20:10ZengAmerican Physical SocietyPhysical Review Research2643-15642022-04-0142L02201410.1103/PhysRevResearch.4.L022014Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in grapheneHamed Koochaki KelardehUlf SaalmannJan M. RostWe identify and describe how intense short light pulses couple to massless Dirac fermions in two-dimensional systems. The ensuing excitation dynamics exhibits unusual scaling with the wavelength of the light due the linear dispersion of the band structure and the fact that light coupling is efficient only close to the Dirac points. We exploit these features to achieve valley polarization of more than 70% with simple pulse shapes. Thereby, we demonstrate that substantial valley polarization at moderate excitation can be achieved with a suitable linearly polarized pulse in gapless systems. Quantitative results are given for pristine graphene.http://doi.org/10.1103/PhysRevResearch.4.L022014 |
| spellingShingle | Hamed Koochaki Kelardeh Ulf Saalmann Jan M. Rost Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene Physical Review Research |
| title | Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene |
| title_full | Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene |
| title_fullStr | Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene |
| title_full_unstemmed | Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene |
| title_short | Ultrashort laser-driven dynamics of massless Dirac electrons generating valley polarization in graphene |
| title_sort | ultrashort laser driven dynamics of massless dirac electrons generating valley polarization in graphene |
| url | http://doi.org/10.1103/PhysRevResearch.4.L022014 |
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