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Manipulating Kondo Temperature via Single Molecule Switching

Violeta Iancu·Aparna Deshpande·Saw -Wai Hla
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Abstract

Two conformations of isolated single TBrPP-Co molecules on a Cu(111) surface are switched by applying +2.2 V voltage pulses from a scanning tunneling microscope tip at 4.6 K. The TBrPP-Co has a spin-active cobalt atom caged at its center and the interaction between the spin of this cobalt atom and free electrons from the Cu(111) substrate can cause a Kondo resonance. Tunneling spectroscopy data reveal that switching from the saddle to a planar molecular conformation enhances spin-electron coupling, which increases the associated Kondo temperature from 130 K to 170 K. This result demonstrates that the Kondo temperature can be manipulated just by changing molecular conformation without altering chemical composition of the molecule.

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Violeta Iancu, Aparna Deshpande, Saw -Wai Hla. 2006-03-08. Manipulating Kondo Temperature via Single Molecule Switching. https://doi.org/10.1021/nl0601886

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