Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices
Abstract Spin current, converted from charge current via spin Hall or Rashba effects, can transfer its angular momentum to local moments in a ferromagnetic layer. In this regard, the high charge‐to‐spin conversion efficiency is required for magnetization manipulation for developing future memory or...
| Main Authors: | , , , , , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2023-04-01
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| Series: | Advanced Science |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/advs.202206800 |
| _version_ | 1797838945432633344 |
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| author | Woo Seung Ham Thi Huynh Ho Yoichi Shiota Tatsuya Iino Fuyuki Ando Tetsuya Ikebuchi Yoshinori Kotani Tetsuya Nakamura Daisuke Kan Yuichi Shimakawa Takahiro Moriyma Eunji Im Nyun‐Jong Lee Kyoung‐Whan Kim Soon Cheol Hong Sonny H. Rhim Teruo Ono Sanghoon Kim |
| author_facet | Woo Seung Ham Thi Huynh Ho Yoichi Shiota Tatsuya Iino Fuyuki Ando Tetsuya Ikebuchi Yoshinori Kotani Tetsuya Nakamura Daisuke Kan Yuichi Shimakawa Takahiro Moriyma Eunji Im Nyun‐Jong Lee Kyoung‐Whan Kim Soon Cheol Hong Sonny H. Rhim Teruo Ono Sanghoon Kim |
| author_sort | Woo Seung Ham |
| collection | DOAJ |
| description | Abstract Spin current, converted from charge current via spin Hall or Rashba effects, can transfer its angular momentum to local moments in a ferromagnetic layer. In this regard, the high charge‐to‐spin conversion efficiency is required for magnetization manipulation for developing future memory or logic devices including magnetic random‐access memory. Here, the bulk Rashba‐type charge‐to‐spin conversion is demonstrated in an artificial superlattice without centrosymmetry. The charge‐to‐spin conversion in [Pt/Co/W] superlattice with sub‐nm scale thickness shows strong W thickness dependence. When the W thickness becomes 0.6 nm, the observed field‐like torque efficiency is about 0.6, which is an order larger than other metallic heterostructures. First‐principles calculation suggests that such large field‐like torque arises from bulk‐type Rashba effect due to the vertically broken inversion symmetry inherent from W layers. The result implies that the spin splitting in a band of such an ABC‐type artificial SL can be an additional degree of freedom for the large charge‐to‐spin conversion. |
| first_indexed | 2024-04-09T15:50:16Z |
| format | Article |
| id | doaj.art-ea450fb3e9974956b85895e2a3f77216 |
| institution | Directory Open Access Journal |
| issn | 2198-3844 |
| language | English |
| last_indexed | 2024-04-09T15:50:16Z |
| publishDate | 2023-04-01 |
| publisher | Wiley |
| record_format | Article |
| series | Advanced Science |
| spelling | doaj.art-ea450fb3e9974956b85895e2a3f772162023-04-26T12:15:35ZengWileyAdvanced Science2198-38442023-04-011012n/an/a10.1002/advs.202206800Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial SuperlatticesWoo Seung Ham0Thi Huynh Ho1Yoichi Shiota2Tatsuya Iino3Fuyuki Ando4Tetsuya Ikebuchi5Yoshinori Kotani6Tetsuya Nakamura7Daisuke Kan8Yuichi Shimakawa9Takahiro Moriyma10Eunji Im11Nyun‐Jong Lee12Kyoung‐Whan Kim13Soon Cheol Hong14Sonny H. Rhim15Teruo Ono16Sanghoon Kim17Institute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanDepartment of Physics University of Ulsan Ulsan 44610 KoreaInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanJapan Synchrotron Radiation Research Institute (JASRI) Sayo Hyogo 679‐5198 JapanJapan Synchrotron Radiation Research Institute (JASRI) Sayo Hyogo 679‐5198 JapanInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanDepartment of Physics University of Ulsan Ulsan 44610 KoreaDepartment of Physics University of Ulsan Ulsan 44610 KoreaCenter for Spintronics Korea Institute of Science and Technology (KIST) Seoul 02792 KoreaDepartment of Physics University of Ulsan Ulsan 44610 KoreaDepartment of Physics University of Ulsan Ulsan 44610 KoreaInstitute for Chemical Research Kyoto University Uji Kyoto 611‐0011 JapanDepartment of Physics University of Ulsan Ulsan 44610 KoreaAbstract Spin current, converted from charge current via spin Hall or Rashba effects, can transfer its angular momentum to local moments in a ferromagnetic layer. In this regard, the high charge‐to‐spin conversion efficiency is required for magnetization manipulation for developing future memory or logic devices including magnetic random‐access memory. Here, the bulk Rashba‐type charge‐to‐spin conversion is demonstrated in an artificial superlattice without centrosymmetry. The charge‐to‐spin conversion in [Pt/Co/W] superlattice with sub‐nm scale thickness shows strong W thickness dependence. When the W thickness becomes 0.6 nm, the observed field‐like torque efficiency is about 0.6, which is an order larger than other metallic heterostructures. First‐principles calculation suggests that such large field‐like torque arises from bulk‐type Rashba effect due to the vertically broken inversion symmetry inherent from W layers. The result implies that the spin splitting in a band of such an ABC‐type artificial SL can be an additional degree of freedom for the large charge‐to‐spin conversion.https://doi.org/10.1002/advs.202206800artificial superlatticebulk Rashba‐type spin splittingcharge‐to‐spin conversionspin current |
| spellingShingle | Woo Seung Ham Thi Huynh Ho Yoichi Shiota Tatsuya Iino Fuyuki Ando Tetsuya Ikebuchi Yoshinori Kotani Tetsuya Nakamura Daisuke Kan Yuichi Shimakawa Takahiro Moriyma Eunji Im Nyun‐Jong Lee Kyoung‐Whan Kim Soon Cheol Hong Sonny H. Rhim Teruo Ono Sanghoon Kim Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices Advanced Science artificial superlattice bulk Rashba‐type spin splitting charge‐to‐spin conversion spin current |
| title | Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices |
| title_full | Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices |
| title_fullStr | Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices |
| title_full_unstemmed | Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices |
| title_short | Bulk Rashba‐Type Spin Splitting in Non‐Centrosymmetric Artificial Superlattices |
| title_sort | bulk rashba type spin splitting in non centrosymmetric artificial superlattices |
| topic | artificial superlattice bulk Rashba‐type spin splitting charge‐to‐spin conversion spin current |
| url | https://doi.org/10.1002/advs.202206800 |
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