Spin-polarized scanning tunneling microscopy with quantitative insights into magnetic probes
Spin-polarized scanning tunneling microscopy and spectroscopy (spin-STM/S) has been successfully applied to magnetic characterizations of individual nanostructures. Spin-STM/S is often performed in magnetic fields of up to some Tesla, which may strongly influence the tip state. In spite of the pivotal role of the tip, the contribution of the tip in spin-STM/S has rarely been investigated in detail. In this talk, an advanced analysis of spin-STM/S data measured on magnetic nanoislands, which relies on a quantitative magnetic characterization of tips, will be discussed. In-field spin-STM on Co bilayer nanoisland on Cu(111) has enabled a quantitative determination, and thereby, a categorization of the magnetic states of the tips. The resulting in-depth and conclusive analysis of magnetic characterization of the tip opens new venues for a clear-cut sub-nanometer scale spin ordering and spin-dependent electronic structure of the non-collinear magnetic state in bilayer high Fe nanoislands on Cu(111).
This work has been performed in collaboration with Dirk Sander, Max-Planck-Institute of Microstructure Physics, Halle, Germany.
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