Switching Behaviour of Pb₅Ge₃O₁₁ Single Crystals

Abstract

Single CrySt8h of lead germanate have been grown by Czochralski method. Hysteresis and switching pulses could only be measured after treating the crystal samples a t elevated temperature and electrical 8.c. field. Hysteresis is strongly frequency dependent. We obaerved the motion of the domain walls in polarized light simultaneously. The hysteresis loop is distorted a t elevated temperature because of electric conductivity of the crystals. Temperature dependence of electric conductivity has been measured.Bleigermanat-Einkrist~le wurden nach der Czochreleki-Methode geziichtet. Erst nach Vorbehandlung der Kristallproben bei erhohter Temperatur im elektrischen Wechselfeld, konnten eine Hysterese und Urnsohaltimpulse gemessen werden. Die Hysterese zeigte eine starke Frequenzabhangigkeit. Gleichzeitig konnte die Bewegung der Domanenw a d e optisch beobachtet werden. Bei erhohter Temperatur verformt sich die Hystereseschleife infolge elektrischer Leitfahigkeit der Kristalle. Die Abhangigkeit der elektrischen Leitfiihigkeit von der Temperatur wurde gemessen.

Effect of uniaxial pressure on the ferroelectric phase transition in Pb5Ge3)11

“…This phenomenon may be connected to the internal structure of the sample, that is to the presence of defects or domain walls. Indeed, the LGO crystals are known as having very small size domains which appear as small hexagons [18,19]. The network of the domain walls may be affected not only by electric field but also by applied stress.…”