Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001)
We report on the mechanism of magnetization reversal in epitaxial Co/Fe bi-layers grown by molecular beam epitaxy on MgO(001) substrates. For Co films thicker than 5 nm, the crystal structure is hexagonal. The Fe layer follows an epitaxial relation relative to the MgO substrate of (001) [100] Fe// (...
| Main Authors: | , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
2008
|
| _version_ | 1826304003569352704 |
|---|---|
| author | Kohn, A Wang, C Petford-Long, A Wang, S Ward, R |
| author_facet | Kohn, A Wang, C Petford-Long, A Wang, S Ward, R |
| author_sort | Kohn, A |
| collection | OXFORD |
| description | We report on the mechanism of magnetization reversal in epitaxial Co/Fe bi-layers grown by molecular beam epitaxy on MgO(001) substrates. For Co films thicker than 5 nm, the crystal structure is hexagonal. The Fe layer follows an epitaxial relation relative to the MgO substrate of (001) [100] Fe// (001) [110] MgO. When deposited on a cubic Fe layer, the Co layer follows a bi-crystal epitaxial relation of (11 2- 0) [0001] Co// (001) 〈 100 〉 Fe as previously reported [Popova, Appl. Phys. Lett. 81, 1035 (2002); Wang, J. Appl. Phys. 101, 09D103 (2007)]. The magnetization reversal in-plane follows a cubic fourfold symmetry, which coincides with that of the underlying bcc Fe layer. In this study, we find that the area of each Co crystal domain spans 200-1500 nm2 and that these two domains are approximately evenly distributed. The micromagnetic reversal mechanism is a combination of coherent rotational processes and domain wall displacement. These magnetic domains are sized tens of μm and separated by predominately 90° or occasionally 180° domain walls along the Fe 〈 110 〉 and Fe 〈 100 〉 directions, respectively. The cubic anisotropy of the bi-crystalline Co layer is explained by exchange-coupling between hcp grains with perpendicular crystallographic orientation, each having in-plane uniaxial magnetic anisotropy along its respective [0001] direction. © 2008 American Institute of Physics. |
| first_indexed | 2024-03-07T06:11:16Z |
| format | Journal article |
| id | oxford-uuid:ef95c221-801c-4f12-a6eb-7acc71c7367d |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T06:11:16Z |
| publishDate | 2008 |
| record_format | dspace |
| spelling | oxford-uuid:ef95c221-801c-4f12-a6eb-7acc71c7367d2022-03-27T11:41:19ZMagnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001)Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:ef95c221-801c-4f12-a6eb-7acc71c7367dEnglishSymplectic Elements at Oxford2008Kohn, AWang, CPetford-Long, AWang, SWard, RWe report on the mechanism of magnetization reversal in epitaxial Co/Fe bi-layers grown by molecular beam epitaxy on MgO(001) substrates. For Co films thicker than 5 nm, the crystal structure is hexagonal. The Fe layer follows an epitaxial relation relative to the MgO substrate of (001) [100] Fe// (001) [110] MgO. When deposited on a cubic Fe layer, the Co layer follows a bi-crystal epitaxial relation of (11 2- 0) [0001] Co// (001) 〈 100 〉 Fe as previously reported [Popova, Appl. Phys. Lett. 81, 1035 (2002); Wang, J. Appl. Phys. 101, 09D103 (2007)]. The magnetization reversal in-plane follows a cubic fourfold symmetry, which coincides with that of the underlying bcc Fe layer. In this study, we find that the area of each Co crystal domain spans 200-1500 nm2 and that these two domains are approximately evenly distributed. The micromagnetic reversal mechanism is a combination of coherent rotational processes and domain wall displacement. These magnetic domains are sized tens of μm and separated by predominately 90° or occasionally 180° domain walls along the Fe 〈 110 〉 and Fe 〈 100 〉 directions, respectively. The cubic anisotropy of the bi-crystalline Co layer is explained by exchange-coupling between hcp grains with perpendicular crystallographic orientation, each having in-plane uniaxial magnetic anisotropy along its respective [0001] direction. © 2008 American Institute of Physics. |
| spellingShingle | Kohn, A Wang, C Petford-Long, A Wang, S Ward, R Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001) |
| title | Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001) |
| title_full | Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001) |
| title_fullStr | Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001) |
| title_full_unstemmed | Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001) |
| title_short | Magnetization reversal processes in epitaxial Co/Fe bi-layers grown on MgO(001) |
| title_sort | magnetization reversal processes in epitaxial co fe bi layers grown on mgo 001 |
| work_keys_str_mv | AT kohna magnetizationreversalprocessesinepitaxialcofebilayersgrownonmgo001 AT wangc magnetizationreversalprocessesinepitaxialcofebilayersgrownonmgo001 AT petfordlonga magnetizationreversalprocessesinepitaxialcofebilayersgrownonmgo001 AT wangs magnetizationreversalprocessesinepitaxialcofebilayersgrownonmgo001 AT wardr magnetizationreversalprocessesinepitaxialcofebilayersgrownonmgo001 |