- Bc. Petr Opletal: Magnetic phases in pseudoternary system UCo1-xRuxAl
- 9. 4. 2014, 14:30
- lecture room F2, first floor Ke Karlovu 5
- more information
Abstract:
UCoAl and URuAl, which crystallize in the hexagonal ZrNiAl-type structure, remain paramagnetic at temperatures at least down to 30 mK. At He temperatures, UCoAl shows a metamagnetic transition at a magnetic field of » 0.6 T applied along the c-axis [1]. Despite the paramagnetism of parent compounds a huge dome of stable ferromagnetism exists over a wide concentration range of pseudoternary UCo1-xRuxAl compounds [2]. For x ³ 0.4, there seems to exist two ferromagnetic phases depending on temperature [2]. We have grown three single crystals of the representative composition x = 0.56, 0.70 and 0.78, respectively, and investigated the character and temperature range of stability of the two ferromagnetic phases by measuring magnetization, electrical resistivity, heat capacity, thermal expansion and thermal transport properties. A scenario will be discussed considering different coherence of the two magnetically ordered phases.
[1] V. Sechovsky and L. Havela, In: Handbook of Ferromagnetic Materials, v. 4, Eds. E.P. Wohlfarth and K.H.J. Buschow (North Holland, Amsterdam, 1988), p. 309-491, and references therein.
[2] A.V. Andreev, at al., Philosophical Magazine B, 75, 827 (1997)