11 research outputs found
Superconductivity and Field-Induced Magnetism in PrCeCuO Single Crystals
We report muon-spin rotation/relaxation (muSR) measurements on single
crystals of the electron-doped high-T_c superconductor PrCeCuO.
In zero external magnetic field, superconductivity is found to coexist with Cu
spins that are static on the muSR time scale. In an applied field, we observe a
Knight shift that is primarily due to the magnetic moment induced on the Pr
ions. Below the superconducting transition temperature T_c, an additional
source of static magnetic order appears throughout the sample. This finding is
consistent with antiferromagnetic ordering of the Cu spins in the presence of
vortices. We also find that the temperature dependence of the in-plane magnetic
penetration depth in the vortex state resembles that of the hole-doped cuprates
at temperatures above ~ 0.2 T_c.Comment: 4 pages, 5 figure
Unusual giant magnetostriction in the ferrimagnet GdCaMnO
We report an unusual giant linear magnetostrictive effect in the ferrimagnet
GdCaMnO (80 K). Remarkably, the
magnetostriction, negative at high temperature (), becomes
positive below 15 K when the magnetization of the Gd sublattice overcomes the
magnetization of the Mn sublattice. A rather simple model where the magnetic
energy competes against the elastic energy gives a good account of the observed
results and confirms that Gd plays a crucial role in this unusual observation.
Unlike previous works in manganites where only striction associated with 3
Mn orbitals is considered, our results show that the lanthanide 4 orbitals
related striction can be very important too and it cannot be disregarded.Comment: 6 pages, 3 figure
Magnetostriktion von Selten-Erd-Verbindungen
SIGLETIB Hannover: DR 2628 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman