Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1612289 | Journal of Alloys and Compounds | 2014 | 9 Pages |
Abstract
Polycrystalline samples of LuAs with a residual resistivity ratio (RRR) between 2.52 and 3.38 were examined by: X-ray diffraction, magnetisation, resistivity, magnetoresistivity, Hall coefficient and thermoelectric power S(T), in addition to the nuclear magnetic resonance (NMR) of 75As and 175Lu nuclei. The density and mobility of carriers for the valence and conduction bands were determined for the RRRÂ =Â 2.52 sample and used for the calculation of thermoelectric power, Sc(T). The value of Sc(T) fits well with that determined by experiment. The sample shows a charge imbalance with the number of electrons n, (holes, p) equal to 1.52Â ÃÂ 1020 (1.12Â ÃÂ 1020)Â e/cm3 at 4Â K. This imbalance decreases with temperature, reversing after passing a minimum at â¼80Â K and then increasing to n (p)Â =Â 9.4Â ÃÂ 1019 (1.42Â ÃÂ 1020)Â e/cm3 at 300Â K. The 75As NMR Knight shift is found to be temperature independent and equal to 0.102% and the 175Lu NMR resonance frequency is shifted to higher values by ca. 0.011% with respect to that of LuSb. All data indicate that LuAs belongs to semimetals and the clearly observed 175Lu NMR multiquadrupolar echoes suggest the existence of defects in the cubic structure of the investigated samples.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
O. Å»ogaÅ, R. Wawryk, M. Matusiak, Z. Henkie,