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Tuning emergent magnetism in a Hund's impurity
A A Khajetoorians1,2, M Valentyuk3,4, M Steinbrecher1
1Department of Physics, Hamburg University, Hamburg D-20355, Germany.
Nature Nanotechnology
|September 8, 2015
Summary
Researchers created a model Hund's impurity using a single iron atom on platinum. This system allows experimental tuning of magnetic properties and exploration of exotic electronic states, advancing the study of correlated electron systems.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Hund's metal describes exotic magnetic and electronic behavior in multi-orbital materials.
- Electron correlations driven by Hund's rule coupling are key.
- Experimentally tuning these materials is challenging.
Purpose of the Study:
- To realize and experimentally investigate a Hund's impurity system.
- To explore the fundamental properties of correlated electron systems.
- To provide a platform for testing advanced many-body theories.
Main Methods:
- Utilized a single iron atom adsorbed on a platinum surface as a model Hund's impurity.
- Employed scanning tunneling microscopy to manipulate the atom's binding site and hydrogenation.
- Probed magnetic excitations and tuned energy scales (Zeeman, temperature, Kondo, anisotropy).
Main Results:
- Successfully realized a system with a magnetic moment and strong charge fluctuations.
- Demonstrated experimental control over magnetic properties via atomic manipulation.
- Tuned the system from an emergent magnetic moment to a multi-orbital Kondo state.
Conclusions:
- A single iron atom on platinum serves as a tunable Hund's impurity.
- This system allows exploration of complex quantum phenomena.
- It offers a novel platform for validating theories of non-Fermi liquids and unconventional superconductivity.
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