Talk given by Prof. Wolfgang Wernsdorfer Nanosciences Department Institut Néel, CNRS Grenoble, France Abstract: Magnetic molecules possess a high potential as building blocks for the design of spintronic devices. Moreover, the use of molecular materials opens the way for the controlled use of bottom-up, e.g. supramolecular, processing techniques combining massively parallel self-fabrication with conventional top-down nanostructuring techniques. Recently, organic semiconductors were inserted into nanometer sized tunnel junctions allowing enhancement of spin reversal, giant magneto-resistance behaviour was observed in single non-magnetic molecules coupled to magnetic electrodes and the use of the quantum tunnelling properties of single-molecule magnets (SMMs) in hybrid devices was proposed. Here, we present an original device in which a non-magnetic molecular quantum dot, made of a single-wall carbon nanotube (SWCNT) contacted with non-magnetic electrodes, is laterally coupled via supramolecular interactions to a TbPc2-SMM (Pc = phthalocyanine), which provides a localized magnetic moment. The conductance through the SWCNT is modulated by sweeping the magnetic field, exhibiting magnetoresistance ratios up to 300% between fully polarized and non-polarized SMMs. Furthermore, we demonstrated that the vibrations of the carbon nanotube guitar string are influenced directly by the magnetic molecule. As the magnetic moment of the molecule changes, the resulting recoil is transferred to the carbon nanotube and the latter starts to vibrate. Vibrations change the atomic distances of the tube and, hence, its electrical conductance which we used as a measure of the nanotube’s motion. As mechanical motion can interact with other phenomena like light or gravitation, one can potentially use it as a mediator to link those phenomena between each other and finally link them to the quantum world. This could lead to completely new applications and alter our picture of the world, as we know it.

This event is part of the eventgroup INT Talks

Homepage
https://www.int.kit.edu/events.php

Speaker
Prof. Wolfgang Wernsdorfer

Institut Neel, CNRS Grenoble
http://neel.cnrs.fr/spip.php?article260&personne=wolfgang.wernsdorfer/nano&lang=en

Organizer
Prof. Mario Ruben
Institut für Nanotechnologie
KIT
Hermann-von-Helmholtz-Platz 1
76344 Eggenstein-Leopoldshafen
Mail: mario ruben ∂does-not-exist.kit edu
https://www.int.kit.edu/1938_mario.ruben.php

Targetgroup
Interested / Everyone