Hamburg 2001 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Tiefe Temperaturen
TT 6: Postersitzung I: Josephsonkontakte und SQUIDs, Supraleitung: Theorie, Korrelierte Elektronen, Niederdimensionale Systeme, Magnetotransport, Quantenhalleffekt, Kohlenstoff-Nanoröhrchen, Quantenflüssigkeiten
TT 6.52: Poster
Montag, 26. März 2001, 14:30–17:00, Rang S\ 3
Quantum Interference of Electrons in Fibrous Ta4Te4Si — •A. Stolovits1, A. Sherman1, K. Ahn2, and R. K. Kremer2 — 1Tartu Ülikooli, Füüsika Instituut, Riia 142, EE-51014 Tartu, Estonia — 2MPI Für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germnay
The crystal structure of the quasi one-dimensional
compound Ta4Te4Si
contains Si centered square antiprismatic Ta4Te4 infinite chains
which are weakly coupled to neighboring chains via Te-Te van der Waals
interaction.
According to band-structure calculations the structure should be stable
and metallic with
two half-filled and a twofold degenerate nearly half-filled conduction
band.
However, early resistivity measurements showed resistivity
characteristics pointing to an
electronic and structural instability in Ta4Te4Si as well.
Here we present a magnetoresistance study of crystalline Ta4Te4Si
fibers (typical thickness < 5 µ m).
Both, the temperature dependence of the
resistivity and the magnetoresistance prove metallic behavior down to
1.7 K.
The low-field magnetoresistance is
interpreted in terms of
three-dimensional anisotropic weak-localization theory. Carrier phase
scattering lengths extracted from the magnetoresistance data are in good
agreement with theoretical predictions for electron-electron
interactions in disordered metals.
Resistivity anomalies previously ascribed to charge density wave like
anomalies are most likely due to crystalline imperfections
induced by electrical current pulses.