A. A. Stepanov

Magnetic cluster formation in Li x Ni 1 − x O compounds: Experiments and numerical simulations

The magnetic properties of

Magnetoelectric studies of antiferromagnetic crystals in strong magnetic fields

{\mathrm{Li}}_{x}{\mathrm{Ni}}_{1\ensuremath{-}x}\mathrm{O}

Observation of the magnetoelectric effect in Gd2CuO4

compounds with x ranging between 0.4 and 0.49 are investigated. Magnetization and ac susceptibility measured at temperatures between 2 K and 300 K reveal a high sensitivity to x, the excess lithium concentration. We introduce a percolation model describing the formation of Ni clusters and use an Ising model to simulate their magnetic properties. Numerical results, obtained by a Monte Carlo technique, are compared to the experimental data. We show the existence of a critical concentration,

Observation of Cu2+ electron spin resonance in Gd2CuO4

{x}_{c}=0.432,

Detection and investigation of AFMR in Gd2CuO4 and GdBa2Cu3Ox

locating the Ni percolation threshold. The system is superparamagnetic for

Magnetic phase transitions in Gd2CuO4 and Sm2CuO4 studied by means of the magnetoelectric effect

xg{x}_{c},

Magnetoelectric effect in Gd2CuO4.

while it is ferrimagnetic for

Origin of the weak ferromagnetism in Gd2CuO4.

xl{x}_{c}.

Spin-orientation phase transitions in Nd2CuO4: A compound with noncollinear magnetic structure.

The

Magnetoelectric effect in R{sub 2}CuO{sub 4} (R=Gd, Sm, and Nd)

180\ifmmode^\circ\else\textdegree\fi{}