Time-resolved photodynamics of triangular-shaped silver nanoplates
Time-resolved photodynamics of triangular-shaped silver nanoplates
复制标题
DOI：
10.1021/nl052131
复制
发表时间：
2006-01-01
期刊：
影响因子：
10.8
通讯作者：
Chergui, M
中科院分区：
文献类型：
--
作者：
Bonacina, L;Callegari, A;Chergui, M
我们测量了三角形银纳米颗粒在飞秒激发等离子体共振时的超快响应。快速电子弛豫后，粒子双峰机械振动的特征明显表现为光谱调制。我们通过对等离子体峰位置和宽度的影响，确定了粒子的两个最低频率、完全对称的振动是造成这种调制的原因，这与所提出的变分弹性动力学模型的结果完全一致。通过对相位的分析，我们得出结论，热膨胀和电子压力分别是激发两种振动的原因。
We measured the ultrafast response of triangular silver nanoparticles upon femtosecond excitation of their plasmon resonance. After a fast electron relaxation, the signature of a bimodal mechanical vibration of the particle is apparent as a spectral modulation. We identify the two lowest frequency, totally symmetric vibrations of the particle as responsible for this modulation, through their influence on the plasmon peak position and width, in full agreement with the results of a variational elastodynamic model that is also presented. From the analysis of the phase we conclude that thermal expansion and electron pressure, respectively, are responsible for the excitation of the two vibrations.