Anisotropy of Magnetic Properties and the Permittivity of Nd1.9Ce0.1CuO4 + δ Single Crystal.

Dielectric and magnetic properties of the Nd_{2– x}Ce_xCuO_{4 + δ} bulk single crystal with x = 0.1 are studied in this work. The anisotropy of the field and temperature dependences of the specific magnetization is found. The value of specific magnetization measured in the magnetic field applied in parallel to CuO₂ planes is higher than that measured in the magnetic field applied perpendicular to the planes; this is related to the additional contribution of magnetic moments of neodymium ions. In this case, at temperatures T < 100 K, when the magnetic field H is perpendicular to CuO₂ planes, an area of antiferromagnetic coupling of ions exists within the CuO₂ planes, which is not observed in the case of the parallel orientation of the magnetic field with respect to the CuO₂ planes. Microwave studies show the existence of strong permittivity dispersion, which indicates the presence of natural resonance frequency, whose value is beyond the frequency range of performed measurements. [ABSTRACT FROM AUTHOR]