Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films
Abstract The Weyl semimetal WTe2 and MoTe2 show great potential in generating large spin currents since they possess topologically protected spin‐polarized states and can carry a very large current density. In addition, the intrinsic non‐centrosymmetry of WTe2 and MoTe2 endows with a unique property...
| Main Authors: | , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2018-06-01
|
| Series: | Advanced Science |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/advs.201700912 |
| _version_ | 1797754236271853568 |
|---|---|
| author | Qisheng Wang Jie Li Jean Besbas Chuang‐Han Hsu Kaiming Cai Li Yang Shuai Cheng Yang Wu Wenfeng Zhang Kaiyou Wang Tay‐Rong Chang Hsin Lin Haixin Chang Hyunsoo Yang |
| author_facet | Qisheng Wang Jie Li Jean Besbas Chuang‐Han Hsu Kaiming Cai Li Yang Shuai Cheng Yang Wu Wenfeng Zhang Kaiyou Wang Tay‐Rong Chang Hsin Lin Haixin Chang Hyunsoo Yang |
| author_sort | Qisheng Wang |
| collection | DOAJ |
| description | Abstract The Weyl semimetal WTe2 and MoTe2 show great potential in generating large spin currents since they possess topologically protected spin‐polarized states and can carry a very large current density. In addition, the intrinsic non‐centrosymmetry of WTe2 and MoTe2 endows with a unique property of crystal symmetry‐controlled spin–orbit torques. An important question to be answered for developing spintronic devices is how spins relax in WTe2 and MoTe2. Here, a room‐temperature spin relaxation time of 1.2 ns (0.4 ns) in WTe2 (MoTe2) thin film using the time‐resolved Kerr rotation (TRKR) is reported. Based on ab initio calculation, a mechanism of long‐lived spin polarization resulting from a large spin splitting around the bottom of the conduction band, low electron–hole recombination rate, and suppression of backscattering required by time‐reversal and lattice symmetry operation is identified. In addition, it is found that the spin polarization is firmly pinned along the strong internal out‐of‐plane magnetic field induced by large spin splitting. This work provides an insight into the physical origin of long‐lived spin polarization in Weyl semimetals, which could be useful to manipulate spins for a long time at room temperature. |
| first_indexed | 2024-03-12T17:29:48Z |
| format | Article |
| id | doaj.art-81087142c23447efbdb30afad7150c04 |
| institution | Directory Open Access Journal |
| issn | 2198-3844 |
| language | English |
| last_indexed | 2024-03-12T17:29:48Z |
| publishDate | 2018-06-01 |
| publisher | Wiley |
| record_format | Article |
| series | Advanced Science |
| spelling | doaj.art-81087142c23447efbdb30afad7150c042023-08-05T03:41:20ZengWileyAdvanced Science2198-38442018-06-0156n/an/a10.1002/advs.201700912Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin FilmsQisheng Wang0Jie Li1Jean Besbas2Chuang‐Han Hsu3Kaiming Cai4Li Yang5Shuai Cheng6Yang Wu7Wenfeng Zhang8Kaiyou Wang9Tay‐Rong Chang10Hsin Lin11Haixin Chang12Hyunsoo Yang13Department of Electrical and Computer Engineering, and NUSNNI National University of Singapore Singapore 117576 SingaporeCenter for Joining and Electronic Packaging State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 ChinaDepartment of Electrical and Computer Engineering, and NUSNNI National University of Singapore Singapore 117576 SingaporeDepartment of Physics National University of Singapore 2 Science Drive 3 Singapore 117542 SingaporeSKLSM Institute of Semiconductors Chinese Academy of Sciences P. O. Box 912 Beijing 100083 ChinaCenter for Joining and Electronic Packaging State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 ChinaCenter for Joining and Electronic Packaging State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 ChinaDepartment of Electrical and Computer Engineering, and NUSNNI National University of Singapore Singapore 117576 SingaporeCenter for Joining and Electronic Packaging State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 ChinaSKLSM Institute of Semiconductors Chinese Academy of Sciences P. O. Box 912 Beijing 100083 ChinaDepartment of Physics National Cheng Kung University Tainan 701 TaiwanDepartment of Physics National University of Singapore 2 Science Drive 3 Singapore 117542 SingaporeCenter for Joining and Electronic Packaging State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 ChinaDepartment of Electrical and Computer Engineering, and NUSNNI National University of Singapore Singapore 117576 SingaporeAbstract The Weyl semimetal WTe2 and MoTe2 show great potential in generating large spin currents since they possess topologically protected spin‐polarized states and can carry a very large current density. In addition, the intrinsic non‐centrosymmetry of WTe2 and MoTe2 endows with a unique property of crystal symmetry‐controlled spin–orbit torques. An important question to be answered for developing spintronic devices is how spins relax in WTe2 and MoTe2. Here, a room‐temperature spin relaxation time of 1.2 ns (0.4 ns) in WTe2 (MoTe2) thin film using the time‐resolved Kerr rotation (TRKR) is reported. Based on ab initio calculation, a mechanism of long‐lived spin polarization resulting from a large spin splitting around the bottom of the conduction band, low electron–hole recombination rate, and suppression of backscattering required by time‐reversal and lattice symmetry operation is identified. In addition, it is found that the spin polarization is firmly pinned along the strong internal out‐of‐plane magnetic field induced by large spin splitting. This work provides an insight into the physical origin of long‐lived spin polarization in Weyl semimetals, which could be useful to manipulate spins for a long time at room temperature.https://doi.org/10.1002/advs.2017009122D materialsspin dynamicsspin polarizationtime‐resolved Kerr rotationWeyl semimetals |
| spellingShingle | Qisheng Wang Jie Li Jean Besbas Chuang‐Han Hsu Kaiming Cai Li Yang Shuai Cheng Yang Wu Wenfeng Zhang Kaiyou Wang Tay‐Rong Chang Hsin Lin Haixin Chang Hyunsoo Yang Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films Advanced Science 2D materials spin dynamics spin polarization time‐resolved Kerr rotation Weyl semimetals |
| title | Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films |
| title_full | Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films |
| title_fullStr | Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films |
| title_full_unstemmed | Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films |
| title_short | Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films |
| title_sort | room temperature nanoseconds spin relaxation in wte2 and mote2 thin films |
| topic | 2D materials spin dynamics spin polarization time‐resolved Kerr rotation Weyl semimetals |
| url | https://doi.org/10.1002/advs.201700912 |
| work_keys_str_mv | AT qishengwang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT jieli roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT jeanbesbas roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT chuanghanhsu roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT kaimingcai roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT liyang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT shuaicheng roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT yangwu roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT wenfengzhang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT kaiyouwang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT tayrongchang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT hsinlin roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT haixinchang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms AT hyunsooyang roomtemperaturenanosecondsspinrelaxationinwte2andmote2thinfilms |