Dielectric properties of an organic ferroelectric of bromide diisopropylammonium embedded into the pores of nanosized Al₂O₃ films

The study presents experimental results for investigating linear and nonlinear dielectric properties of nanocomposites based on bromide diisopropylammonium (C₆H₁₆NBr, DIPAB) and aluminum oxide films (Al₂O₃) with pore diameter of 330, 100 and 60 nm. It was indicated that the phase transition was blurred and shifted toward lower temperatures. This anomaly became more significant with decreasing pore size. The reduction of phase transition temperature in the nanocomposites, containing DIPAB, was consistent with theoretical models for the influence of size effects on the structural phase transition. (paper)