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1，3，5-三硫杂-2，4，6-三氮杂并环戊二烯基（TTTA）晶体中发现了一个大的一级磁相变，并且在很宽的温度范围内具有很宽的热滞回线，有机自由基晶体有望成为一种具有光诱导相变（PIPT）现象的新型强关联电子体系.本论文研究了在不同光子密度和波长的双光子吸收下，TTTA晶体的光致发光和光诱导抗磁-顺磁相变，探索了如何在具有较大光学非线性的纳米和微米区域内控制TTTA的磁性质，并为利用PIPT现象开发功能纳米和微米机械提供了一条新的途径。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，抗磁性到顺磁性的相变有效地发生，具有大的转换产率和陡峭的响应，而不是光致发光的发生，这表明相变是由具有大的光学非线性的双光子吸收光学诱导的。利用TTTA的大非线性PIPT行为，可以在室温下对TTTA的磁性能进行控制，并将其分散到UV固化树脂中，用于双光子微立体光刻制备三维微机械，以开发功能化的纳米和微机械。我们发现，TTTA可以成功地分散到树脂保持PIPT特性的飞秒再生放大器的强激光脉冲的照射。

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