Control of Magnetic Properties in Nano- and Micro-scales with Large Optical Nonlinearity: a New Approach for Development of Functional Micromachines

具有大光学非线性的纳米和微米尺度磁特性控制：功能微机械开发的新方法

• 批准号: 17310068
• 负责人: TAKEDA Jun
• 金额: $ 9.84万
• 依托单位: Yokohama National University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17310068/
• 关键词: Organic Radical; TTTA; Two-Photon Absorption; Photoinduced Phase Transition; Optical Nonlinearity; Magnetic Control; Micro-Machine

Since a large first order magnetic phase transition with a wide thermal hysteresis loop over wide temperature range was found in 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA) crystal, an organic radical crystal is expected to be a new type of strong correlated electronic systems showing photoinduced phase transition (PIPT) phenomena. In this research, we explore how to control the magnetic properties of TTTA in nano- and micro-regions with large optical nonlinearity, and demonstrate a new approach for the development of functional nano and micromachines by utilizing the PIPT phenomena.Photoluminescence as well as photoinduced diamagnetic to paramagnetic phase transition in TTTA crystal has been studied in detail under two-photon absorption with different photon densities and wavelengths. Below the threshold photon density to drive the PIPT, the diamagnetic phase shows a broad luminescence band with a large Stokes shift, whose intensity obeys almost second power law of the excitation photon density. Above the threshold photon density, on the other hand, the diamagnetic to paramagnetic phase transition effectively takes place with a large conversion yield and a steep response instead of an occurrence of the photoluminescence, indicating that the phase transition is optically induced by two-photon absorption with large optical nonlinearity. Using the PIPT behavior with the large nonlinearity, the magnetic properties of TTTA can be controlled at room temperature.In order to develop the functional nano and micromachines, TTTA is distributed into UV curable resins, which are suitable for the production of 3D micromachines by using two-photon microstereolithography. We found that TTTA can be successfully distributed into the resins with keeping the PIPT characteristics by irradiation of intense laser pulses from a femtosecond regenerative amplifier.

由于在1,3,5-三硫-2,4,6-三氮杂五烯基（TTTA）晶体中发现了在宽温度范围内具有宽热滞回线的大一阶磁相变，因此有机自由基晶体有望成为一种表现出光致相变（PIPT）现象的新型强相关电子系统。在本研究中，我们探索了如何在具有大光学非线性的纳米和微米区域控制TTTA的磁特性，并展示了利用PIPT现象开发功能性纳米和微米机械的新方法。在不同光强的双光子吸收下，详细研究了TTTA晶体的光致发光以及光致抗磁性到顺磁性的相变。 光子密度和波长。在驱动 PIPT 的阈值光子密度以下，抗磁相显示出具有大斯托克斯位移的宽发光带，其强度几乎服从激发光子密度的二次幂定律。另一方面，在阈值光子密度以上，反磁到顺磁相变有效地发生，具有大的转换产率和陡峭的响应，而不是发生光致发光，这表明相变是由具有大光学非线性的双光子吸收引起的。利用大非线性的PIPT行为，可以在室温下控制TTTA的磁性能。为了开发功能性纳米和微米机械，将TTTA分散到UV固化树脂中，适合使用双光子微立体光刻技术生产3D微型机械。我们发现，通过飞秒再生放大器的强激光脉冲照射，TTTA 可以成功地分布到树脂中，同时保持 PIPT 特性。

项目成果

Time- and Frequency-resolved Two-dimensional Transient Absorption Imaging B-Carotene in Solids

固体中 B-胡萝卜素的时间和频率分辨二维瞬态吸收成像

• 期刊: Ultrafast Phenomena XV, Springer Series in Chemical Physics. (印刷中)(accepted)
• 作者: J.Takeda;Y.Makishima;A.Ishida
• 通讯作者: A.Ishida

光物性の基礎と応用

光学物理基础与应用

• 发表时间: 2006
• 作者: M.Sugisaki;T.Sashima;K.Yanagi;A.Sugita;H.Hashimoto;杉崎 満 他
• 通讯作者: 杉崎 満 他

Luminescence Properties and Relaxation Processes of Strongly Correlated Organic Radical 'ITTA Crystals and Molecules

强相关有机自由基ITTA晶体和分子的发光性质和弛豫过程

• 发表时间: 2008
• 期刊: Journal of Luminescence 128
• 作者: H. Suzuki;et. al.
• 通讯作者: et. al.

Direct Visualization of Transient Absorption by Real-Time Pump-Probe Imaging Spectroscopy

通过实时泵浦探针成像光谱直接可视化瞬态吸收

• 发表时间: 2004
• 期刊: Ultrafast Phenomena(Springer, Tokyo) XIV(印刷中)
• 作者: N.Furukawa;C.E.Mair;V.D.Kleiman;J.Takeda
• 通讯作者: J.Takeda

Femtosecond real-time pump-probe imaging spectroscopy implemented on a single shot basis

• DOI: 10.1143/jjap.45.5986
• 发表时间: 2006-07-01
• 期刊: JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS
• 作者: Makishima, Yoshinori;Furukawa, Naoki;Takeda, Jun
• 通讯作者: Takeda, Jun