Research progress in rare earth doping photoluminescent ferroelectric thin films

Abstract

Rare earth doping is an important method to improve the properties of optoelectronic functional materials. Combining rare earth doping ferroelectric materials and rare earth photoluminescence can create new functional properties of ferroelectric materials. For example, choosing and using an appropriate rare earth element to be doped into a bismuth titanate ferroelectric material, the bismuth titanate will exhibit good photoluminescent properties as well as ferroelectric properties. Recently, photoluminescence properties originating from rare earth ions in oxide ferroelectric materials have attracted much attention for possible integrated photoluminescent ferroelectric device applications. In this paper, we briefly review the research status and progress of photoluminescence in rare earth photoluminescent ferroelectric materials, and we place the emphasis on our own research work in photoluminescent ferroelectric thin films such as (Bi,Eu)₄Ti₃O₁₂, (Bi,Er)₄Ti₃O₁₂, and codoped bismuth titanate thin films, and nanocomposite (Bi,Eu)₄Ti₃O₁₂ ferroelectric thin films. Our results show that the rare earth doped bismuth titanate ferroelectric thin films exhibit good photoluminescent and ferroelectric properties due to unique compositions and layered perovskite structure, that the Eu³⁺ fluorescent structure probe can provide a new path for further studying the relationship between structure and property of Eu-doped ferroelectric thin films, that the rare earth photoluminescence can be used to examine the existence of morphotropic phase boundary in certain ferroelectric thin films such as Pr-doped <i>x</i>(K_1/2Bi_1/2)TiO₃-(1－<i>x</i>)(Na_1/2Bi_1/2)TiO₃ thin films, and nanocomposite materials of ZnO nanomaterials, and that Au nanoparticles, Ag nanoparticles with Eu-doped bismuth titanate exhibit obviously enhanced photoluminescent properties.