Jeong Young Jin, Jeong Do Gyeom, Ju Hwiin, Choi In Hyeok, Roh Chang Jae, Lee Jin Hong, Yang Chan-Ho, Lee Jong Seok
Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
Sci Rep. 2024 Oct 16;14(1):24309. doi: 10.1038/s41598-024-75597-6.
We investigated the multi-domain states of a multiferroic La-doped BiFeO (BLFO) thin film by examining diffraction patterns in optical second-harmonic generation (SHG) measurement. By directing a laser onto the domain wall within the domain-patterned sample, we observed clear diffraction signatures of SHG waves generated from two ferroelectric domains. We explained the experimental results of the diffraction patterns, including the intensity distribution and the polarization characteristics, using Fresnel propagation of SHG waves. From this, we could determine the amplitude and phase of the SHG waves generated from each domain, and figure out not only the polarization direction of each ferroelectric domain but also the phase related to the complex-valued second-order susceptibility tensor. Consequently, we could present SHG diffractometry as an effective measurement method to reveal the phase details of electric polarization of the multi-domain states of ferroic materials.
我们通过研究光学二次谐波产生（SHG）测量中的衍射图案，对多铁性掺镧铋铁氧体（BLFO）薄膜的多畴状态进行了研究。通过将激光对准畴图案化样品内的畴壁，我们观察到了由两个铁电畴产生的SHG波的清晰衍射特征。我们利用SHG波的菲涅耳传播来解释衍射图案的实验结果，包括强度分布和偏振特性。由此，我们可以确定每个畴产生的SHG波的振幅和相位，不仅可以确定每个铁电畴的偏振方向，还可以确定与复值二阶极化率张量相关的相位。因此，我们可以将SHG衍射测量法作为一种有效的测量方法，以揭示铁性材料多畴状态下电极化的相位细节。
