Dresden 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Tiefe Temperaturen
TT 11: Postersitzung II (Metall-Isolator-Überg
änge, Phasenüberg
änge in Quantensystemen, Theorie: Systeme korrelierter Elektronen)
TT 11.19: Poster
Dienstag, 25. März 2003, 14:30–19:00, P2c, P2d
Electronic transport and structural properties of electronically correlated CuV2S4 — •R. Horny, S. Klimm, M. Klemm, S. Ebbinghaus, G. Eickerling, and S. Horn — Institut f. Physik, Universität Augsburg, 86159 Augsburg, Germany
The metallic thiospinel CuV2S4 is isostructural to the heavy fermion
system LiV2O4 with formally the same number (1.5) of d-electrons per
V atom. Its Sommerfeld coefficient γ=62 mJ/molK2 is comparable to
that of V2O3. A charge density wave (CDW) transition at
TCDW=90 K has been observed in CuV2S4 single crystals. In
polycrystalline samples, however, at T=90 K a structural transition into
a tetragonal phase has been reported.
We present an investigation of temperature dependent structural, magnetic,
and transport properties of single- and polycrystalline samples. Our
polycrystals exhibit sharp phase transitions and a residual resistance
ratio of RRR=10. Below T=10 K the resistivity follows a T2 behavior.
Resistivity measurements were also performed under hydrostatic pressure.
Both the 90 K
transition as well as a second hysteretic transition at T=55 K shift to
higher temperatures with increasing pressure.
Our single crystals were thoroughly characterized by X-ray diffraction and
proofed to be of high quality. However, they only show a smooth variation
of resistivity with RRR=1.1 and no sharp phase transitions.
The relations between structure, stoichiometry, and physical properties are
discussed.
This work was supported by DFG (SFB 484).