Conventionally, photoluminescence (PL) properties are mainly modulated through traditional chemical approaches which are ex situ, irreversible and static modulation techniques, potentially limiting the understanding of the detailed process of luminescence and smart PL applications. Here, an in situ dynamic routine is developed to tune the PL response in an epitaxial Yb³⁺/Er³⁺ co-doped BaTiO₃ thin film through electric-field-induced strain of a piezoelectric single-crystal Pb(Mg_1/3Nb_2/3)O₃–PbTiO₃ (PMN–PT) substrate. A reversible tuning and enhancement of the PL intensity was achieved when an external electric field was applied to the PMN–PT single-crystal substrate. The underlying mechanism responsible for the dynamic enhancement of the PL intensity was attributed to the strain induced lower host symmetry so as to enhance the hypersensitive transition probability of the rare-earth ions. The present work could provide a significant guide for the in situ dynamic and active modulation of the PL performances of luminescent devices through the piezoelectric strain.

中文翻译：

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通过Pb（Mg _1/3 Nb _2/3）O ₃ -PbTiO ₃单晶引起的压电应变对外延薄膜的光致发光进行可逆的原位调节

常规上，光致发光（PL）特性主要通过传统的化学方法进行调制，这些方法是非原位，不可逆和静态调制技术，可能会限制对发光和智能PL应用的详细过程的理解。在此，开发了一种原位动态程序，通过电场诱导的压电单晶Pb（Mg _1/3）的应变来调节外延Yb ³⁺ / Er ³⁺共掺杂的BaTiO ₃薄膜中的PL响应。Nb _2/3）O ₃ –PbTiO ₃（PMN–PT）基材。当在PMN-PT单晶衬底上施加外部电场时，PL强度可逆调节和增强。导致PL强度动态增强的潜在机制归因于应变引起的较低的主体对称性，从而增强了稀土离子的超敏跃迁几率。本工作可为通过压电应变对发光器件的PL性能进行原位动态和主动调制提供重要指导。