Pyroelectric properties of TGS with internal bias field

Abstract

Pyroelectric properties of triglycine sulphate (TGS) grown at ferroelectric phase as a function of temperature are reported. Measurements are performed on virgin samples during cooling. It is shown that the degree of unipolarity of the sample is equal to one at short‐circuit condition and below one when the depolarization field is comparable with the internal bias field. The value of the internal bias field is also determined.

Pyroelectric properties of phosphoric acid-doped TGS single crystals

“…In the case of phosphoric acid-doped samples, since the peak dielectric constant values were already smeared (table 1) to a great extent by the internal bias field, the influence of the surface layer effect was not so significant (figures 6 and 7). The value of E b for TGS (1400 V m −1 ) is found to be high in comparison with the value (220 V m −1 ) [29] and low in comparison with the values 3000-15 000 V m −1 [21] reported earlier.…”

Investigation of the pyroelectric and piezoelectric properties of triglycine sulphate single crystals containing organic molecules

“…The value of the internal bias may be estimated from the peak value, pmax, of the pyroelectric coefficient using the following equation (Pykacz 1978) where la( T -To) and E/4 are the coefficients of the terms P2 and P 4 in the free-energy expansion under an external field and P is the polarisation. The values of a and were computed for the crystals used in the present investigation (Gaffer et a1 1989) and hence the internal bias could be estimated.…”