Linear electro-optic effect induced by synergistic light and electric fields in paraelectric Mn&Fe: KTN single crystals

Electro-optic (EO) devices play an important role in various optical fields including optical communications and optical sensing. As the core of EO devices, the properties of EO materials determine the application performance of EO devices. Designing more diversified regulation schemes to achieve larger EO effects is the key to improve current performance. Here, we propose a method by synergistic light and electric fields to induce the linear EO effect in the paraelectric Mn/Fe co-doped KTa1−xNbxO3 (Mn&Fe: KTN) single crystals. After co-modulation of light and electric fields, an effective linear EO coefficient of 170 pm/V is obtained in the paraelectric Mn&Fe: KTN crystal (TC = 10 °C). The constructed internal electric field and stress in the illuminated area are characterized and analyzed to be the reason for the induced linear EO effect. This study provides an approach for inducing erasable linear EO effect in paraelectric crystals, which is beneficial for material design in many optical devices including optical modulator and optical memory.