Development of novel photo-dielectric materials

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K18855
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 21:Electrical and electronic engineering and related fields
• Research Institution: Nagoya University
• Principal Investigator: Taniguchi Hiroki 名古屋大学, 理学研究科, 准教授 (80422525)
• Project Period (FY): 2018-06-29 – 2021-03-31
• Keywords: 誘電体 / 光誘起効果 / 光電効果 / アルミネート

Outline of Final Research Achievements

We have explored novel dielectric materials with the photo-dielectric effect, the dielectric permittivity of which varies with photo-irradiation, and have studied a mechanism of the photo-tunability. Through extensive investigations, we have found considerable enhancement of permittivity in reduced LaAlO3 under the photo-irradiation, and have clarified that oxygen vacancies play an important role in the observed photo-dielectric effect. In the modified BaAl2O4, which was subjected to slight element-substitution, furthermore, we have found that the dielectric relaxation of the photo-dielectric effect around 107 Hz. By analyzing the observed dielectric relaxation, it has been clarified that the photo-dielectric effect stems from the polarization response of photo-excited carriers trapped at the multiple in-gap states.

Free Research Field

固体物性物理学

Academic Significance and Societal Importance of the Research Achievements

トランジスタや青色LEDに代表されるように、新しいデバイス素子の創出は科学技術の新展開を常に先導してきた。本研究は、光－誘電応答相関の基礎学理構築を通して、光によって誘電体の特性を自在にコントロールする、これまでに例の無い全く新しいデバイス素子の創製に取り組むものである。誘電体は、周波数フィルタやセンサなどへの応用を通して現代の電子デバイスに遍く応用されており、言うなれば「エレクトロニクス技術の米」とも言うべき物質系である。したがって、本研究で実現する誘電体の光制御は、従来のエレクトロニクスから次世代のフォトエレクトロニクスへの不連続な技術革新を先導すると期待される。