Optical spin-transfer-torque-driven domain-wall motion in a ferromagnetic semiconductor

Ramsay, A.J.; Roy, P.E.; Haigh, J.A.; Otxoa, R.M.; Irvine, A.C.; Janda, T.; Campion, R.P.; Gallagher, B.L.; Wunderlich, J.

Abstract

We demonstrate optical manipulation of the position of a domain wall in a dilute magnetic semiconductor,GaMnAsP. Two main contributions are identified. First, photocarrier spin exerts a spin-transfer torque on the magnetization via the exchange interaction. The direction of the domain-wall motion can be controlled using the helicity of the laser. Second, the domain wall is attracted to the hot spot generated by the focused laser. Unlike magnetic-field-driven domain-wall depinning, these mechanisms directly drive domain-wall motion, providing an optical tweezerlike ability to position and locally probe domain walls.

Citation

Ramsay, A., Roy, P., Haigh, J., Otxoa, R., Irvine, A., Janda, T., …Wunderlich, J. (2015). Optical spin-transfer-torque-driven domain-wall motion in a ferromagnetic semiconductor. Physical Review Letters, 114(6), Article 067202. https://doi.org/10.1103/PhysRevLett.114.067202

• Journal Article Type: Article
• Acceptance Date: Jan 13, 2015
• Online Publication Date: Feb 11, 2015
• Publication Date: Feb 13, 2015
• Deposit Date: Aug 8, 2016
• Publicly Available Date: Aug 8, 2016
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 114
• Issue: 6
• Article Number: 067202
• DOI: https://doi.org/10.1103/PhysRevLett.114.067202
• Public URL: https://nottingham-repository.worktribe.com/output/745155
• Publisher URL: http://dx.doi.org/10.1103/PhysRevLett.114.067202