[9p-N201-1~14] 6.1 Ferroelectric thin films

2:15 PM - 2:30 PM JST(5:15 AM - 5:30 AM UTC)

[9p-N201-4] Asymmetric Effect on Pyroelectric Hysteresis Curve of LiTaO₃ Single Crystal

〇Jun Usami¹, Yoshiomi Hiranaga², Hiroyuki Yamada¹ (1.AIST, 2.Tohoku Univ.)

Keywords:

Ferroelectricity

Previous work on PZT thin films revealed polarization-direction-dependent asymmetries in both pyroelectric and electrocaloric effects, which were attributed to non-switchable polarization from domain pinning; however, analogous asymmetries in single crystals remain unexamined. In this study, we measured the voltage-dependent hysteresis of pyroelectric and electrocaloric responses in 1 μm-thick LiTaO₃ single crystals. Although Li-vacancy defect dipoles produce an internal bias that shifts the hysteresis along the voltage axis, the polarization-axis response remains symmetric. This contrasts with PZT films and suggests that in LiTaO₃, defect dipoles serve solely to generate bias, allowing nearly complete polarization reversal under the applied field.