Speaker
Level for award<br> (Hons, MSc, <br> PhD)?
PhD
Apply to be<br> considered for a student <br> award (Yes / No)?
Yes
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?
Yes
Abstract content <br> (Max 300 words)
In recent years interest in quantum critical behaviour (QCB) has intensified, as is reflected in literature [1,2,3]. A quantum critical point (QCP) is typically found in a material where the phase transition temperature has been driven or tuned to zero by the application of a tuning parameter such as magnetic field, pressure or through doping [1]. Previous studies on the (Cr84Re16)100-yVyalloy system, utilizing doping as a tuning parameter, showed the existence of a putative QCP at a critical concentration yc of about 10.5 [4].The present study extends these results by focusing on the antiferromagnetic alloy with y = 10.4 and using a new tuning parameter. The (Cr84Re16)89.6V10.4 alloy has a concentration very close to yc and possible QCB in this sample is investigated through the application of magnetic field. Magnetic susceptibility (χ)was measured as function of temperature (T) in the temperature range 1.9 K < T < 200 K. The sample was cooled to 2 K in zero field, followed by measurements being collected upon warming the sample in static applied fields (H)in the range 0.01 T to 6.5 T. The χ(T)curves obtained for the various applied fields each show a clear peak and the temperature associated with the peak was taken as the Néel temperature (TN). Results indicate that the sharpness of the peak improves with
field and that the application of field suppresses TN. The TN(H)curve shows a sharp gradient up to 2 T of approximately -6.177 K/T. In the region 2 T < H < 6 T a gradient of approximately -1.823 K/T is observed, above which the TN(H)curve tends to level off. Interesting conclusions are drawn from the present work and future investigations utilizing higher fields are proposed.
[1] Lee M, Husmann A, Rosenbaum TF and Aeppli G 2004 Phys. Rev. Lett. 92 187201
[2] Yeh A, Soh Y, Brooke J, Aeppli G and Rosenbaum TF 2002 Nature 419 459
[3] Takeuchi J, Sasakura H and Masuda Y 1980 J. Phys. Soc. Japan 49 508
[4] Jacobs BS, Prinsloo ARE, Sheppard CJ and Strydom AM 2013 J.Appl.Phys. 113 17E126
Main supervisor (name and email)<br>and his / her institution
Prof ARE Prinsloo
alettap@uj.ac.za
University of Johannesburg
