Constant current: A method for obtaining hysteresis loops in ferroelectricmaterials

A new method is proposed to obtain hysteresis loops in ferroelectric materi als in which the sample is submitted to a constant electric current. This t echnique was applied on poly(vinylidene fluoride), PVDF, biaxially stretche d samples and the hysteresis loops of the electric displacement and electri c polarization versus the electric field compared well with those obtained with the Sawyer-Tower method. The constant current method is advantageous i n that no measuring amplifiers are needed and it is insensitive to prebreak down noise. (C) 1999 American Institute of Physics. [S0034-6748(99)04806-6] .