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arXiv · 2008.03119

Anisotropic Ultrafast Spin Dynamics in Epitaxial Cobalt

Vivek Unikandanunni·Rajasekhar Medapalli·Eric E. Fullerton·Karel Carva·Peter M. Oppeneer·Stefano Bonetti
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Abstract

We investigate the ultrafast spin dynamics in an epitaxial hcp(1100) cobalt thin film. By performing pump-probe magneto-optical measurements with the magnetization along either the easy or hard magnetic axis, we determine the demagnetization and recovery times for the two axes. We observe a 35% slower dynamics along the easy magnetization axis, which we attribute to magneto-crystalline anisotropy of the electron-phonon coupling, supported by our ab initio calculations. This points towards an unambiguous and previously undisclosed role of anisotropic electron-lattice coupling in ultrafast magnetism.

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Vivek Unikandanunni, Rajasekhar Medapalli, Eric E. Fullerton, Karel Carva, Peter M. Oppeneer, Stefano Bonetti. 2020-08-07. Anisotropic Ultrafast Spin Dynamics in Epitaxial Cobalt. https://doi.org/10.1063/5.0049692

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