Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase
We investigate ultrafast phonon dynamics in the Bi _1− _x Sb _x alloy system for various compositions x using a reflective femtosecond pump-probe technique. The coherent optical phonons corresponding to the A _1 _g local vibrational modes of Bi–Bi, Bi–Sb, and Sb–Sb are generated and observed in the...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2021-01-01
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| Series: | New Journal of Physics |
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| Online Access: | https://doi.org/10.1088/1367-2630/abe2c0 |
| _version_ | 1797750194703433728 |
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| author | Yuta Komori Yuta Saito Paul Fons Muneaki Hase |
| author_facet | Yuta Komori Yuta Saito Paul Fons Muneaki Hase |
| author_sort | Yuta Komori |
| collection | DOAJ |
| description | We investigate ultrafast phonon dynamics in the Bi _1− _x Sb _x alloy system for various compositions x using a reflective femtosecond pump-probe technique. The coherent optical phonons corresponding to the A _1 _g local vibrational modes of Bi–Bi, Bi–Sb, and Sb–Sb are generated and observed in the time domain with a few picoseconds dephasing time. The frequencies of the coherent optical phonons were found to change as the Sb composition x was varied, and more importantly, the relaxation time of those phonon modes was dramatically reduced for x values in the range 0.5–0.8. We argue that the phonon relaxation dynamics are not simply governed by alloy scattering, but are significantly modified by anharmonic phonon–phonon scattering with implied minor contributions from electron–phonon scattering in a Weyl-semimetal phase. |
| first_indexed | 2024-03-12T16:30:12Z |
| format | Article |
| id | doaj.art-1d920cb560b2414ab5816714b4036796 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:30:12Z |
| publishDate | 2021-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-1d920cb560b2414ab5816714b40367962023-08-08T15:32:18ZengIOP PublishingNew Journal of Physics1367-26302021-01-0123202303410.1088/1367-2630/abe2c0Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phaseYuta Komori0Yuta Saito1https://orcid.org/0000-0002-9576-1560Paul Fons2https://orcid.org/0000-0002-7820-1924Muneaki Hase3https://orcid.org/0000-0003-4242-2546Department of Applied Physics, Faculty of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba 305-8573, JapanDevice Technology Research Institute, National Institute of Advanced Industrial Science and Technology , Tsukuba Central 5, 1-1-1 Higashi, Tsukuba 305-8565, JapanDevice Technology Research Institute, National Institute of Advanced Industrial Science and Technology , Tsukuba Central 5, 1-1-1 Higashi, Tsukuba 305-8565, Japan; Department of Electronics and Electrical Engineering, Faculty of Science and Technology, Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, JapanDepartment of Applied Physics, Faculty of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba 305-8573, JapanWe investigate ultrafast phonon dynamics in the Bi _1− _x Sb _x alloy system for various compositions x using a reflective femtosecond pump-probe technique. The coherent optical phonons corresponding to the A _1 _g local vibrational modes of Bi–Bi, Bi–Sb, and Sb–Sb are generated and observed in the time domain with a few picoseconds dephasing time. The frequencies of the coherent optical phonons were found to change as the Sb composition x was varied, and more importantly, the relaxation time of those phonon modes was dramatically reduced for x values in the range 0.5–0.8. We argue that the phonon relaxation dynamics are not simply governed by alloy scattering, but are significantly modified by anharmonic phonon–phonon scattering with implied minor contributions from electron–phonon scattering in a Weyl-semimetal phase.https://doi.org/10.1088/1367-2630/abe2c0coherent phononphonon scatteringultrafast spectroscopytopological materials |
| spellingShingle | Yuta Komori Yuta Saito Paul Fons Muneaki Hase Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase New Journal of Physics coherent phonon phonon scattering ultrafast spectroscopy topological materials |
| title | Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase |
| title_full | Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase |
| title_fullStr | Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase |
| title_full_unstemmed | Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase |
| title_short | Ultrafast scattering dynamics of coherent phonons in Bi1−x Sb x in the Weyl semimetal phase |
| title_sort | ultrafast scattering dynamics of coherent phonons in bi1 x sb x in the weyl semimetal phase |
| topic | coherent phonon phonon scattering ultrafast spectroscopy topological materials |
| url | https://doi.org/10.1088/1367-2630/abe2c0 |
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