F18

26.06, 17:20-17:40

Straumal B.B., Schütz G., Goering E., Baretzky B., Mazilkin A.A., Protasova S.G., Myatiev A.A., Straumal P.B.
Grain-boundary induced ferromagnetism in doped and undoped nanocrystalline zinc oxide.

Russia / Россия

Zinc oxide has a definite threshold value, s_th, of specific area of intercrystalline boundaries (grain boundaries, GBs), s_GB. If the s_GB < s_th, ZnO is paramagnetic. If s_GB < s_th, ZnO is ferromagnetic. Using the novel “liquid ceramic” method we succeeded to obtain dense (poreless) nanocrystalline ZnO films with GB specific area above s_th. These films possess very reproducible ferromagnetic behaviour and T_c above room temperature.