TGS单晶电畴运动的微分回线谱分析

微分电滞回线谱方法可分出铁电体中漏电导、非铁电性电容的影响而得到纯铁电机构运动的信息.采用该方法对硫酸三甘肽(TGS)单晶进行研究,确认单晶铁电畴的生长速度与外加电压的峰值大小和周期都密切相关.要想得到给定样品的完整电滞回线,外加电压需大于样品的矫顽电压,信号频率应尽可能小.否则,根据不完整电滞回线得到的极化强度、矫顽场等信息是错误的.对于厚度为0.50mm的TGS样品,频率需小于10Hz,电场峰值需大于1.2kV/cm,比矫顽场大30%.

Differential hysteresis loop analysis for domain motion of TGS

Differential hysteresis loop spectroscopy could eliminate the influence of DC conductance and non-ferroelectric capacitance,therefore could reveal the effects of pure ferroelectricity.This method was used to study the ferroelectric properties of triglycine sulfate（TGS）.It was revealed that the grow speed of ferroelectric domain in TGS was strongly related to both the peak voltage and frequency of external field.If wanted to obtain a perfect loop of a given sample,peak voltage must be higher than coercive voltage as well as the frequency must be low enough.Otherwise,spontaneous polarization and coercive field obtained from the imperfect loop were inaccurate.For the TGS sample with a thickness of 0.50 mm,the frequency must be lower than 10 Hz,and peak electric field must be higher than 1.2 kV/cm,as well as 30% higher than reported coercive field.