In Situ Electric Field Tuning Photoluminescence Response in Tetragonal-Phase Ferroelectric Single Crystals

Ferroelectric single crystals with photoluminescence (PL) response are of great interest in the development of advanced multifunctional optoelectronic devices due to their special PL, ferroelectric, piezoelectric, and strain properties. Previous reports have focused on these ferroelectric ceramics. However, the physical mechanism of tuning the PL properties and the effect of symmetry and domain switching in ferroelectric materials are not clear. Here, the PL of Yb3+-doped tetragonal-phase ferroelectric single crystals are studied. The in situ modulating PL response under an external electric field shows that the PL intensity varies in four stages before becoming saturated with an enhancement of 16.7%. The variation in the PL intensity confirms the domain rotation using the in situ observation of domain evolution. We demonstrate that the rotation of the 90° domain is the main reason for the increase in PL intensity and offer a physical schematic diagram for explanation. This work presents a paradigm for studying the modulation of PL properties via engineered domain ferroelectric single crystals for potentially multifunctional materials for optoelectronic devices.