Hamburg 2001 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
AM: Magnetismus
AM 9: Poster: Magnetowid. (1-17), Dü. Schichten (18-34), Oberfl
ächenmag. (35,36), Mikr. Methoden (37-45), Mikromag. (46-58), Phasenüberg. (59-77), Spektroskop. (78-91), Nanokr.Mat.(92-96), Anisotrop. (97-101), Schmelzen(102-104),Sonst/postdeadl.(105-109)
AM 9.105: Poster
Dienstag, 27. März 2001, 14:45–19:00, Foyer S 3
Influence of Substitutions of Mn on Charge and Magnetic Ordering in Ca-doped Manganites — •N.V. Kasper1,2, N. Hamad1, A. Kattwinkel1, K. Bärner1, I.O. Troyanchuk2, D.D. Khalyavin2, G.H. Rao3, J.R. Sun3, and H. Szymczak4 — 14.Phys. Inst. Uni-Göttingen, Bunsenstr.11-15, 37073 Göttingen — 2Inst. of Solids and Semicond. Phys., P. Brovka Str.17, 220072 Minsk, BELARUS — 3Inst. of Phys. and Cent. for Cond. Matter Phys., Beijing 100080, CHINA — 4Inst. of Phys. PAN, al. Lotnikow 32/46, 02-668 Warsaw, POLAND
Magnetic and transport properties of charge-ordered manganites R1−xCaxMn1−yMeyO3 (R=Pr, Nd, 0.4≤ x ≤ 0.8) depending on replacement of Mn with Me=Fe, Cr, Al, Ti, and Nb were studied. It is shown, that all substitutions suppress the charge ordered state in parent Me-free compounds. Slightly Cr-doped compounds (0.04≤ y ≤ 0.1) show metal-insulator and antiferromagnet-ferromagnet phase transitions. An inhomogeneos magnetic state with activate type of conductivity develops at higher Cr-concentrations and in Fe-doped compounds. Mn-Cr and Mn-Fe exchange couplings are found to be negative. The substitutions with non-magnetic ions Al3+, Ti4+, Nb5+ lead to semiconductive spin-glass states.