| We suggest a possible mechanism for the description of magnetic friction in non-contact atomic force microscopy experiments on magnetic systems. We consider the interaction of an atomically sharp tip with a spin as an external perturbation acting on a two-state quantum system coupled to a bosonic bath. In the framework of the real-time path integral treatment of the driven spin-boson model, we investigate the behaviour and frequency dependence of the energy loss for different regimes and couplings. In particular we focus on the hysteretic regime, as the best candidate to explain nonvanishing dissipation for frequencies very low compared to the natural time scales of the isolated system, which is the interesting limit for typical AFM setups. |
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