Investigation of nonlinear dielectric properties of the multiferroic CuO

The dielectric properties of the multiferroic CuO were studied by the nonlinear dielectric spectroscopy. It is shown that the dielectric constant and dielectric loss tangent increase with a temperature increase. Dependencies ε'( T ) and tgδ( T ) have insignificant anomalies at the transition temperature Т N2 = 230 K. The maximum values ​​of the second and third harmonics occur in the middle of the temperature range [ Т N1 ; Т N2 ].