Roughness effects in uncompensated antiferromagnets
Abstract
Monte Carlo simulations show that roughness in uncompensated antiferromagnets decreases not just the surface magnetization but also the net magnetization and particularly strongly affects the temperature dependence. In films with step-type roughness, each step creates a new compensation front that decreases the global net magnetization. The saturation magnetization decreases non-monotonically with increasing roughness and does not scale with the surface area. Roughness in the form of surface vacancies changes the temperature-dependence of the magnetization; when only one surface has vacancies, the saturation magnetization will decrease linearly with surface occupancy, whereas when both surfaces have vacancies, the magnetization is negative and exhibits a compensation point at finite temperature, which can be tuned by controlling the occupancy. Roughness also affects the spin-texture of the surfaces due to long-range dipolar interactions and generates non-collinear spin configurations that could be used in devices to produce locally modified exchange bias. Lastly, these results explain the strongly reduced magnetization found in magnetometry experiments and furthers our understanding of the temperature-dependence of exchange bias.
- Authors:
-
- Univ. of California, Berkeley, CA (United States). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Division; Federal Inst. of Technology, Zurich (Switzerland). Lab. of Metal Physics and Technology
- Univ. of California, Berkeley, CA (United States). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Division
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- OSTI Identifier:
- 1512172
- Alternate Identifier(s):
- OSTI ID: 1228199
- Grant/Contract Number:
- AC02-05CH11231
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Applied Physics
- Additional Journal Information:
- Journal Volume: 117; Journal Issue: 8; Journal ID: ISSN 0021-8979
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Charilaou, M., and Hellman, F. Roughness effects in uncompensated antiferromagnets. United States: N. p., 2015.
Web. doi:10.1063/1.4913594.
Charilaou, M., & Hellman, F. Roughness effects in uncompensated antiferromagnets. United States. https://doi.org/10.1063/1.4913594
Charilaou, M., and Hellman, F. Wed .
"Roughness effects in uncompensated antiferromagnets". United States. https://doi.org/10.1063/1.4913594. https://www.osti.gov/servlets/purl/1512172.
@article{osti_1512172,
title = {Roughness effects in uncompensated antiferromagnets},
author = {Charilaou, M. and Hellman, F.},
abstractNote = {Monte Carlo simulations show that roughness in uncompensated antiferromagnets decreases not just the surface magnetization but also the net magnetization and particularly strongly affects the temperature dependence. In films with step-type roughness, each step creates a new compensation front that decreases the global net magnetization. The saturation magnetization decreases non-monotonically with increasing roughness and does not scale with the surface area. Roughness in the form of surface vacancies changes the temperature-dependence of the magnetization; when only one surface has vacancies, the saturation magnetization will decrease linearly with surface occupancy, whereas when both surfaces have vacancies, the magnetization is negative and exhibits a compensation point at finite temperature, which can be tuned by controlling the occupancy. Roughness also affects the spin-texture of the surfaces due to long-range dipolar interactions and generates non-collinear spin configurations that could be used in devices to produce locally modified exchange bias. Lastly, these results explain the strongly reduced magnetization found in magnetometry experiments and furthers our understanding of the temperature-dependence of exchange bias.},
doi = {10.1063/1.4913594},
journal = {Journal of Applied Physics},
number = 8,
volume = 117,
place = {United States},
year = {Wed Feb 25 00:00:00 EST 2015},
month = {Wed Feb 25 00:00:00 EST 2015}
}
Web of Science
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