Time-delayed emission in TPCO crystals based on quantum coherence

2015 Fiscal Year Final Research Report

• Project/Area Number: 25286042
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Applied materials
• Research Institution: Nara Institute of Science and Technology
• Principal Investigator: Yanagi Hisao 奈良先端科学技術大学院大学, 物質創成科学研究科, 教授 (00220179)
• Co-Investigator(Kenkyū-buntansha): KATSUKI Hiroyuki 奈良先端科学技術大学院大学, 物質創成科学研究科, 准教授 (10390642)
• Co-Investigator(Renkei-kenkyūsha): SASAKI Fumio 独立行政法人産業技術総合研究所, 電子光技術研究部門, 上級主任研究員 (90222009) ; HOTTA Shu 京都工芸繊維大学, 大学院工芸科学研究科, 教授 (00360743)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: TPCO結晶 / 遅延発光 / 超放射 / 量子コヒーレンス / 有機レーザー

Outline of Final Research Achievements

In order to clarify the origin of time-delayed pulse emission observed for TPCO crystals, we investigated crystal structure and size dependence of this phenomenon using TPCO derivatives. As compared to BP1T which crystallized in a monoclinic form, a cyano-substituted derivative, BP1T-CN, crystallized in a triclinic form and showed a shorter delay time. Raman scattering spectroscopy of AC5 and BP3T crystals indicated that coherent molecular vibrations were involved in their amplified emission processes. Using size-controlled p-6P crystals, it was found that the fluorescence lifetime and threshold excitation fluence decreased as the crystal size was reduced. From these findings, we discussed that uniaxially oriented molecular packing in the TPCO crystals brought about strong light-exciton interaction mediated by molecular vibrations even in a macroscopic scale of 100 micrometer.

Free Research Field

有機フォトニクス