Dielectric spectroscopy in para-ferro transition of TGS

abstract

Triglycine sulphate crystal (TGS) is one of the most studied ferroelectric materials, having a second order transition around 49°C. The complex dielectric constant we have measured on the frequency range 1–10⁷ Hz and on a large temperature range, in ferroelectric phase after the para - ferro transition. Temperature was monitored from room temperature to 65°C, were for 30 min it was kept constant and then was lowered down at a rate of 0.6°C/min. Both component of permittivity were automatically registered. This study was focused on the dielectric relaxation processes. Three fundamental relaxation mechanisms (LF, MF, and HF) were found and analyzed with the Cole-Cole functions. The activation energy of these relaxation mechanisms have been estimated in the ferroelectric phase

KEYWORDS:

• Triglycine sulphate; relaxation in ferroelectric phase; activation energy; dielectric strength