Development of photo-excited dielectric relaxation method : selective and quantitative analyses of excitation and relaxation processes of photoactive sites.

稀土掺杂半导体是光电器件的热点材料之一。提出了一种利用电子技术分析材料发光机理的新方法，即光激发介电弛豫（PEDR）。建立了PEDR的实验装置。该装置成功地实现了Sm掺杂TiO2发光基本过程的选择性和定量分析。此外，还确定了引起猝灭的电荷耗散过程。研究了TiO2微晶的界面态对其致发光和猝灭的影响。

Rare-earth doped semiconductors are one of topical materials for opto-electric devices. I proposed a new analytical technique of luminescence mechanisms of the materials by using an electronic technique, namely, photo excited dielectric relaxation(PEDR). An experimental setup for PEDR was developed. Selective and quantitative analyses of elementary processes for luminescence of Sm doped TiO2 were successfully realized with the setup. Moreover, charge dissipation processes that cause quenching were identified. Interface states of TiO2 microcrystals which induce luminescence and quenching were characterized.