| dc.creator |
Valkass, Robert Alexander James |
|
| dc.creator |
Shelford, Leigh R |
|
| dc.creator |
Durrant, Chris J |
|
| dc.creator |
Figueroa, Adriana |
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| dc.creator |
Baker, Alex A |
|
| dc.creator |
Shafer, Padraic |
|
| dc.creator |
Arenholz, Elke |
|
| dc.creator |
Childress, Jeffrey R |
|
| dc.creator |
Katine, Jordan A |
|
| dc.creator |
van der Laan, Gerrit |
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| dc.creator |
Hicken, Robert J |
|
| dc.date |
2016-03-31T09:27:25Z |
|
| dc.date |
2016-04-04 |
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| dc.identifier |
http://hdl.handle.net/10871/20893 |
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| dc.description |
Poster presented at Magnetism 4 – 5 April 2016, Sheffield. |
|
| dc.description |
In spin valve structures the damping of a ferromagnetic layer driven at resonance can be modified by the transfer of spin angular momentum into a ‘sink’ ferromagnetic layer. This effect, known as spin pumping, is interface dominated and expected to increase with increasing sink layer thickness up to a saturation absorption depth, previously reported to be 1.2 nm regardless of the sink layer’s composition [1]. Using vector network analyser ferromagnetic resonance (VNA-FMR), we have studied the variation in damping as a function of sink layer thickness in a series of CoMnGe (5 nm) / Ag (6 nm) / NiFe (x nm) spin valves. These measurements show only small variations in the CoMnGe Gilbert damping parameter for x ≤ 1.8 nm, although damping is observed to increase at x = 0.3 and 0.6 nm. Element-resolved x-ray detected ferromagnetic resonance (XFMR) [2] measurements confirm spin transfer torque due to spin pumping as the origin of the damping for x = 1.5 and 1.8 nm, with both thicknesses having the same effective spin mixing conductance, supporting the findings of Ghosh et al [1]. For thicker sink layers the source and sink FMR fields are seen to coincide, hampering the identification of spin pumping.
[1] A Ghosh, et al. Physical Review Letters 109, 127202 (2012)
[2] M Marcham, et al. Physical Review B 87, 180403 (2013) |
|
| dc.description |
We thank the Advanced Light Source for access to beamlines 4.0.2 and 6.3.1 (ALS-06433, ALS-07116). The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. |
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| dc.description |
We thank Diamond Light Source for access to beamlines I06 and I10 (SI8782, SI11585, SI13063) that contributed to the results presented here. |
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| dc.description |
This work was supported by the Engineering and Physical Sciences Research Council [grant number EP/J018767/1]. |
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| dc.language |
en |
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| dc.publisher |
University of Exeter |
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| dc.relation |
http://magnetism2016.iopconfs.org/home |
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| dc.rights |
This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License. To view a copy of this license, please visit http://creativecommons.org/licenses/by-sa/4.0/ |
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| dc.rights |
2016-04-04 |
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| dc.rights |
Embargoed until the day of the conference. |
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| dc.subject |
Research Subject Categories::NATURAL SCIENCES |
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| dc.subject |
Research Subject Categories::NATURAL SCIENCES::Physics |
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| dc.subject |
Research Subject Categories::NATURAL SCIENCES::Physics::Condensed matter physics |
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| dc.subject |
Research Subject Categories::NATURAL SCIENCES::Physics::Condensed matter physics::Magnetism |
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| dc.subject |
Research Subject Categories::NATURAL SCIENCES::Physics::Condensed matter physics::Surfaces and interfaces |
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| dc.title |
Effect of sink layer thickness on damping in CoMnGe (5 nm) / Ag (6 nm) / NiFe (x nm) spin valves |
|
| dc.type |
Presentation |
|