AC and DC conductivity around the ferroelectric phase transition in (CH₃NH₃)₃Bi₂Br₉ (MABB) crystal

Abstract

The temperature dependence of dc and ac conductivity in the vicinity of T_c3 = 112.5 K (on heating) for the MABB crystal was measured. For ac conductivity the frequencies between 20 Hz and 1 MHz were applied. The behaviour of conductivity was explained by means of power law [sgrave]_ac = [sgrave]_dc + Aω^p, where ω is the frequency and p ≪ 1. The activation energies both for dc and ac conductivity were estimated.

Key Words:

• Ferroelectrics, dc conductivity, ac conductivity, ionic conductors