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Mechanical dissipation from charge and spin transitions in oxygen-deficient SrTiO₃ surfaces.

ABSTRACT: Bodies in relative motion separated by a gap of a few nanometers can experience a tiny friction force. This non-contact dissipation can have various origins and can be successfully measured by a sensitive pendulum atomic force microscope tip oscillating laterally above the surface. Here, we report on the observation of dissipation peaks at selected voltage-dependent tip-surface distances for oxygen-deficient strontium titanate (SrTiO₃) surface at low temperatures (T = 5 K). The observed dissipation peaks are attributed to tip-induced charge and spin state transitions in quantum-dot-like entities formed by single oxygen vacancies (and clusters thereof, possibly through a collective mechanism) at the SrTiO₃surface, which in view of technological and fundamental research relevance of the material opens important avenues for further studies and applications.

SUBMITTER: Kisiel M

PROVIDER: S-EPMC6063934 | biostudies-literature |

REPOSITORIES: biostudies-literature

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