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Published on: September 19, 2017
Switching of a coupled spin pair in a single-molecule junction
Stefan Wagner1, Ferdinand Kisslinger, Stefan Ballmann
1Lehrstuhl für Angewandte Physik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstrasse 7, D-91058 Erlangen, Germany.
Nature Nanotechnology
|July 16, 2013
Summary
Researchers detected coupled spin pairs in single magnetic molecules. Applying bias voltage allowed switching between pseudo-singlet and pseudo-triplet states, advancing molecular spintronics control.
Area of Science:
- Quantum physics
- Materials science
- Nanotechnology
Background:
- Single-molecule spintronics explores electron transport in magnetic molecules.
- Understanding and controlling molecular spin states is crucial.
- The Kondo effect, a low-temperature anomaly, is observed for unpaired spins.
Purpose of the Study:
- To detect coupled spin pairs within a single magnetic molecule.
- To demonstrate voltage-controlled switching between molecular spin states.
Main Methods:
- Utilized the mechanically controlled break-junction technique for single-molecule junction measurements.
- Employed spin-orbit configuration interaction methods for theoretical calculations.
- Analyzed low-temperature electronic transport and conductance data.
Main Results:
- Successfully detected a coupled spin pair in a single molecule with two Co(2+) centers.
- Identified pseudo-singlet ground and pseudo-triplet excited states via theoretical calculations.
- Correlated these states with the presence or absence of a Kondo-like zero-bias anomaly.
- Demonstrated repeatable switching between states using applied bias voltage.
Conclusions:
- Established a method for detecting and manipulating coupled spin states in single molecules.
- Showcased voltage-induced switching between distinct spin configurations.
- Opened new avenues for controlling quantum phenomena at the molecular level.
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