Optical Scattering Spectral Thermometry and Refractometry of a Single Gold Nanoparticle under CW Laser Excitation
Optical Scattering Spectral Thermometry and Refractometry of a Single Gold Nanoparticle under CW Laser Excitation
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DOI：
10.1021/jp304271d
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发表时间：
2012-07
影响因子：
3.7
通讯作者：
K. Setoura;D. Werner;S. Hashimoto
中科院分区：
文献类型：
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作者：
K. Setoura;D. Werner;S. Hashimoto
基于暗场显微镜的白色光散射光谱是研究单个贵金属纳米粒子局域表面等离子体共振的有力工具，也是开发其在传感和生物医学治疗中应用的有力工具。在这里，我们展示了一个单一的金纳米粒子在连续激光加热下的稳态散射光谱的变化。实验峰位移允许在300-700 K范围内的粒子温度的估计与±20 K的精度的基础上，利用米氏理论的光谱计算。对于单一的金纳米粒子支持在玻璃基板上，在空气中观察到渐进的红移，而在水和甘油中观察到蓝移随着温度的升高。由于距离相关的纳米级介质加热，介质对峰位移有很大的影响：位移强烈依赖于介质折射率的温度系数的大小。峰值位移的激光功率依赖行为揭示了…
White light scattering spectra based on dark-field microscopy is a powerful tool for studying localized surface plasmon resonances of single noble metal nanoparticles and for developing their applications in sensing and biomedical therapies. Here we demonstrate the steady-state scattering spectral changes of a single gold nanoparticle under continuous laser heating. The experimental peak shifts allowed the estimation of the particle temperature in the range of 300–700 K with an accuracy of ±20 K on the basis of a spectral calculation exploiting Mie theory. For single gold nanoparticles supported on a glass substrate, progressive red shifts were observed in air, whereas blue shifts were observed in water and glycerol with increasing temperature. The medium has strong influence on peak shifts because of distance-dependent nanoscale medium heating: the shifts strongly depend on the magnitude of the temperature coefficients of a medium refractive index. The laser power-dependent behavior of peak shifts reveal...