001     136360
005     20231031115515.0
020 _ _ |a 978-3-89336-740-5
024 7 _ |2 sirsi
|a (Sirsi) a292164
024 7 _ |2 ISSN
|a 1866-1807
024 7 _ |2 Handle
|a 2128/4522
024 7 _ |2 altmetric
|a altmetric:82625702
037 _ _ |a PreJuSER-136360
041 _ _ |a English
082 _ _ |a 500
082 _ _ |a 600
100 1 _ |0 P:(DE-Juel1)VDB78497
|a Goß, Karin
|b 0
|e Corresponding author
|g female
|u fzj
245 _ _ |a Interactions between parallel carbon nanotube quantum dots
260 _ _ |a Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag
|c 2011
300 _ _ |a VIII, 139 S.
336 7 _ |0 PUB:(DE-HGF)3
|2 PUB:(DE-HGF)
|a Book
|m book
336 7 _ |2 DRIVER
|a book
336 7 _ |0 1
|2 EndNote
|a Book
336 7 _ |2 DataCite
|a Output Types/Book
336 7 _ |2 ORCID
|a BOOK
336 7 _ |2 BibTeX
|a BOOK
490 0 _ |0 PERI:(DE-600)2445293-2
|a Schriften des Forschungszentrums Jülich. Reihe Schlüsseltechnologien / key technologies
|v 30
500 _ _ |a Record converted from JUWEL: 18.07.2013
502 _ _ |a Universität Duisburg, Diss., 2011
|b Dr.
|c Universität Duisburg
|d 2011
520 _ _ |a The subject of this thesis is molecular interactions which are investigated using the example of parallel quantum dots formed in the individual strands of a carbon nanotube rope. For molecular electronics, carbon nanotubes offer a variety of macromolecular structures and by combining several nanotubes into a rope, also a generic system to probe molecular interactions. First, the structure of the contacted rope is characterized by tip-enhanced Raman spectroscopy (TERS). We observe a clear resonance effect for the Raman scattering process, which is up to now not considered in the literature on TERS of carbon nanotubes. By extracting the diameter, metallicity and chirality, seven carbon nanotubes within the rope are identified. A redshift of their optical transition energies is attributed to interactions between the strands. In quantum transport measurements, the nanotubes are found to form interacting parallel quantum dots. Within the framework of master equations, a model is developed to describe the transport via the quantum dot system, where the parallel dots are capacitively and tunnel coupled. Employing this model, seven parallel quantum dots are characterized by their interactions. Along with changing interface properties predicted by the TERS characterization, the coupling to the two contacts is very asymmetric for most of the quantum dots. Additionally, the coupling to the gate electrode is found to vary strongly for individual dots, allowing one to tune the quantum dot system into different configurations and selectively add electrons to individual strands of the rope. Exploiting this differential gating effect, the magnitude of the molecular interactions can be investigated. Here, we find that individual strands within one carbon nanotube rope can interact very distinctly. Amongst the coupled quantum dots with a coupling stronger than previously assumed, we also find only capacitively interacting or completely uncoupled quantum dots within the one device. The tunnel coupling is a hybridization of quantum dot states which, in principle, are comprised of the molecular orbitals. In particular, the sign of the hybridization amplitude contains information about the involved wavefunctions, where we always find a negative amplitude denoting the overlap of wavefunctions with the same sign. The hybridization can be manipulated by an applied magnetic field and hence selectively suppressed due to spin effects. Here, the differential gating allows for tuning to distinct spin configurations of the quantum dot system. In conclusion, we demonstrate a tunable quantum device which provides the possibility of probing molecular interactions by quantum transport spectroscopy. The additional characterization using TERS represents a novel combination of two experimental techniques with great potential in the field of molecular electronics.
856 4 _ |u https://juser.fz-juelich.de/record/136360/files/Schluesseltech_30.pdf
|y OpenAccess
856 4 _ |u https://juser.fz-juelich.de/record/136360/files/Schluesseltech_30.jpg?subformat=icon-1440
|x icon-1440
|y OpenAccess
856 4 _ |u https://juser.fz-juelich.de/record/136360/files/Schluesseltech_30.jpg?subformat=icon-180
|x icon-180
|y OpenAccess
856 4 _ |u https://juser.fz-juelich.de/record/136360/files/Schluesseltech_30.jpg?subformat=icon-640
|x icon-640
|y OpenAccess
909 C O |o oai:juser.fz-juelich.de:136360
|p openaire
|p open_access
|p driver
|p VDB
|p dnbdelivery
914 1 _ |y 2013
915 _ _ |0 StatID:(DE-HGF)0510
|2 StatID
|a OpenAccess
920 _ _ |l yes
920 1 _ |0 I:(DE-Juel1)PGI-6-20110106
|k PGI-6
|l Elektronische Eigenschaften
|x 0
970 _ _ |a 2128/4522
980 _ _ |a I:(DE-Juel1)PGI-6-20110106
980 _ _ |a UNRESTRICTED
980 _ _ |a JUWEL
980 _ _ |a ConvertedRecord
980 _ _ |a VDB
980 _ _ |a book
980 _ _ |a FullTexts
980 1 _ |a FullTexts


LibraryCollectionCLSMajorCLSMinorLanguageAuthor
Marc 21