Investigation of oscillator strength enhancement of electric dipole forbidden transitions in optical near field

光近场电偶极子禁戒跃迁振子强度增强研究

• 批准号: 17340121
• 负责人: HASUO Masahiro
• 金额: $ 9.7万
• 依托单位: Kyoto 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-17340121/
• 关键词: Optical near field; Electric quadrupole transition; Magnetic dipole transition; Oscillator strength; FDTD method; Cu_2O; Exciton

1 Estimation of electric dipole forbidden transition efficiency in optical near fields generated by a sub-wavelength slit arrayOptical near fields generation by a periodically structured 50 nm width slit array of a 50 nm thick gold film were calculated with the FDTD (Finite Difference Time Domain) method, which was developed in this project. The efficiencies of the electric quadrupole (E2) and magnetic dipole (M1) transitions, which are modified by the gradient of the excitation light field, were evaluated for the calculated optical fields. The E2 transition efficiency is largely enhanced in the case where the light polarization of the incident light is perpendicular to the slit direction while such enhancement is not seen for the M1 transition in this polarization. The large enhancement of the E2 transition efficiency mainly originates from the field concentration and the large spatial modulation at the slit edge. In the case where the incident light is parallel to the slit, the enhan … More cement is small for both the E2 and Ml transition, which is consistent with the modification factor of (k_0ld)^<-2>, where K_0 and d are the wavenumber of the homogenously propagating light in vacuum and the slit width, respectively. The enhancement of the E2 excitation efficiency was also calculated for the 1s-ortho exciton in Cu_2O in the optical near field generated by a sub-wavelength slit array. It was suggested that the enhancement is affected by the surface plasmon resonance.2 Observation of emission spectra of the 1s-ortho exciton in Cu_2O through a sub-wavelength slit arrayWith an electron beam lithographic method, a periodically structured gold slit array with 50 nm thickness was fabricated on a Cu_2O crystal surface. We confirmed that the emissions of the electric quadrupole (E2) and dipole (El) transitions of the 1s-ortho excitons in Cu_2O can be observed through the slit array. So far, effects of the slit array to the E2 emission have not been detected. The polarization and slit-period dependences of the emission intensities were observed.3 Observation of the magnetic dipole transition of O_2We developed a spectroscopic system with a dipole laser to observe the light absorption due to the magnetic dipole (M1) transition of O_2 (A-band, 763 nm). In order to make the system high sensitive, we merged the system with an off-axis cavity. It was confirmed that the absorption spectrum can be measured with sufficient spectral resolution. The effect of multi-reflection in the cavity for the increase in the sensitivity was also confirmed. Less

1通过通过FDTD（有限差差时间域）方法计算了由50 nm厚金膜的定期结构结构的50 nm宽度狭缝阵列估算由子波长度狭缝阵列近场生成的近波长缝隙阵列近场生成的估算。对计算出的光场评估了电场梯度修饰的电二极管（E2）和磁偶极（M1）跃迁的效率。如果入射光的光垂直于缝隙方向，而在此极化中未看到M1转变，则E2过渡效率在很大程度上得到了增强。 E2过渡效率的较大增强主要来自场浓度和狭缝边缘处的大空间调制。在入射光与缝隙平行的情况下，Enhan…对于E2和ML过渡而言，更多的水泥较小，这与（K_0LD）^<-2>的修饰因子一致，其中K_0和D分别是真空和缝隙中的均质繁殖光的波形。还计算了E2兴奋的增强，还计算了由子波长狭缝阵列生成的光学接近场中的1s-ortho刺激。 2通过次波长缝阵列阵列以电子束光刻法的阵列（一种定期结构结构的金缝阵列）在CU_2O晶体晶体表面上构造了50 nm厚度，对Cu_2O中1s-ortho Inventon的发射光谱进行了观察。我们证实，可以通过缝隙阵列观察到Cu_2O中1S-Ortho激子的电气四极（E2）和偶极子（EL）跃迁的发射。到目前为止，尚未检测到缝隙阵列对E2发射的影响。 3观察O_2We的磁性偶极转变开发了具有偶极激光的光谱系统，以观察由于O_2（M1）O_2（A-Band，763 NM）的磁性滥用，从而观察到了光谱系统。为了使系统高灵敏，我们将系统与离轴腔合并。已确认可以通过足够的光谱分辨率测量抽象光谱。还确认了腔中多反射对敏感性增加的影响。较少的

项目成果

微小開口アレイによって生成される近接場光のシミュレーション

微孔径阵列产生的近场光的模拟

• 发表时间: 2005
• 作者: 奥田倫弘;出口和広;中村浩章;澤田圭司;岩前敦;蓮尾昌裕
• 通讯作者: 蓮尾昌裕

Relaxation of fluorescence polarization by radiation re-absorption in a near field regime

通过近场区域中的辐射重吸收来弛豫荧光偏振

• 发表时间: 2006
• 作者: M. Okuda;K. Deguchi;A. Iwamae;H. Nakamura;K. Sawada and M. Hasuo;K. Deguchi and M. Hasuo
• 通讯作者: K. Deguchi and M. Hasuo

微小スリットアレイにおける光の透過と近接場光の生成

微缝阵列中的光传输和近场光产生

• 发表时间: 2005
• 作者: 奥田倫弘;岩前敦;出口和広;中村浩章;澤田圭司;蓮尾昌裕
• 通讯作者: 蓮尾昌裕

半導体上金属薄膜ナノ開口における光伝播のシミュレーション

半导体金属薄膜纳米孔径中光传播的模拟

• 发表时间: 2006
• 作者: 奥田倫弘;出口和広;中村浩章;澤田圭司;岩前敦;蓮尾昌裕
• 通讯作者: 蓮尾昌裕

微小スリット列を通した亜酸化銅1sオルソ励起子発光の観測

通过微缝阵列观察氧化亚铜1s正激子发射

• 发表时间: 2007
• 作者: 田中晋平;出口和広;岩前敦;中村浩章;澤田圭司;蓮尾昌裕
• 通讯作者: 蓮尾昌裕