We deposited polar-axis-oriented tetragonal and rhombohedral single domain Pb(Zr, Ti)O₃ (PZT) films on CaF₂(100) substrates by inserting SrRuO₃ (SRO)/LaNiO₃ and SRO/SrTiO₃/TiO₂/CeO₂ buffer layers. Both PZT films grew epitaxially and had a (001)- and (111)-domain with the remnant polarization and piezoelectric constant comparable to the theoretical values of PZT single crystals having the same compositions. The electro-optic (EO) response of the fabricated PZT films was constant with respect to the DC electric field and increased linearly with an increasing AC electric field, thus representing a typical linear EO response in single domain ferroelectrics. The measured EO coefficients were larger than the value for a single crystal of PbTiO₃, i.e., one of the end members of PZT, but smaller than the values reported for polycrystalline and epitaxial PZT films with multiple domains. These findings show that the intrinsic EO effect is enhanced in PZT, which is similar to the enhancement seen in the dielectric and piezoelectric constants. Moreover, most of the reported EO response in PZT films is supported by additional extrinsic contributions.

中文翻译：

---

揭示单畴 Pb(Zr, Ti)O3 薄膜的固有电光效应

我们通过插入 SrRuO ₃ (SRO)/LaNiO ₃和 SRO/SrTiO ₃ /TiO ₂ /在 CaF ₂ (100) 衬底上沉积了极轴取向的四方和菱面体单畴 Pb(Zr, Ti)O ₃ (PZT) 薄膜氧化铈₂缓冲层。两种 PZT 薄膜均外延生长并具有 (001)-和 (111)-畴，其剩余极化和压电常数与具有相同成分的 PZT 单晶的理论值相当。制造的 PZT 薄膜的电光 (EO) 响应相对于直流电场是恒定的，并且随着交流电场的增加而线性增加，因此代表了单畴铁电体中典型的线性 EO 响应。测得的 EO 系数大于 PbTiO ₃单晶的值，即 PZT 的最终成员之一，但小于报告的多晶和外延 PZT 薄膜的值。这些发现表明，固有 EO 效应在 PZT 中得到增强，这类似于在介电常数和压电常数中看到的增强。此外，大多数报道的 PZT 薄膜中的 EO 响应得到了额外的外在贡献的支持。