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arXiv · 1010.4880

Atomic spin sensitive dissipation on magnetic surfaces

Franco Pellegrini·Giuseppe E. Santoro·Erio Tosatti
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Abstract

We identify the mechanism of energy dissipation relevant to spin-sensitive nanomechanics including the recently introduced magnetic exchange force microscopy, where oscillating magnetic tips approach surface atomic spins. The tip-surface exchange couples spin and atom coordinates, leading to a spin-phonon problem with Caldeira-Leggett type dissipation. In the overdamped regime, that can lead to a hysteretic flip of the local spin with a large spin-dependent dissipation, even down to the very low experimental tip oscillation frequencies, describing recent observations for Fe tips on NiO. A phase transition to an underdamped regime with dramatic drop of magnetic tip dissipation should in principle be possible by tuning tip-surface distance.

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Franco Pellegrini, Giuseppe E. Santoro, Erio Tosatti. 2010-10-23. Atomic spin sensitive dissipation on magnetic surfaces. https://doi.org/10.1103/physrevlett.105.146103

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