12-15 July 2011
Saint George Hotel
Africa/Johannesburg timezone

Exploratory investigation of spin density wave behaviour of a (Cr<sub>86</sub> Re<sub>14</sub>)<sub>100-y</sub> V<sub>y</sub> alloy system

13 Jul 2011, 17:00
2h
Asteria

Asteria

Poster Presentation Track A - Condensed Matter Physics and Material Science Poster1

Speaker

Mrs Bincy Susan Jacobs (University Of Johannesburg)

Description

The Cr-Re alloy system was chosen in order to investigate a previous observation of the co-existence of superconductivity and antiferromagnetism, as well as the possibility of a quantum critical point (QCP) in this alloy system. For the initial studies a Cr86Re14 mother alloy was doped with V in order to decrease the electron to atom ratio, resulting in a decrease in the Néel temperature (TN). The preliminary study focused on first obtaining a pure body centered cubic (BCC) Cr86Re14 mother alloy, as in this alloy system, a secondary A15 phase may co-exist. X-ray diffraction and electron microprobe analyses of as-cast and annealed samples revealed only BCC structure with good homogeneity and actual Re concentration of 16 ± 1 atomic percent. In order to initiate investigations into the magnetic properties and possible quantum criticality in this system, electrical resistivity and magnetic susceptibility measurements as a function of temperature are reported for (Cr86Re14)100-yVy alloys with y = 0, 5, 7 and 9. Electrical resistivity as a function of temperature for these samples reveal an anomaly on cooling through TN. The anomaly observed shifts down to lower temperatures as the V concentration is increased. Magnetic susceptibility data supports these observations. These promising results warrant further investigation into this alloy system with the possibility of contributing towards the current interest in quantum criticality in chromium alloy systems.

Consider for a student <br> &nbsp; award (Yes / No)? No
Level (Hons, MSc, <br> &nbsp; PhD, other)? PhD
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)? No

Primary author

Mrs Bincy Susan Jacobs (University Of Johannesburg)

Co-authors

Prof. Aletta Prinsloo (University Of Johannesburg) Prof. Andre Strydom (University Of Johannesburg) Dr Charles Sheppard (University Of Johannesburg)

Presentation Materials