Superparamagnetic Magnetite Nanoparticle Superstructures for Optical Modulation/Chopping
Superparamagnetic Magnetite Nanoparticle Superstructures for Optical Modulation/Chopping
复制标题
用于光调制/斩波的超顺磁性磁铁矿纳米粒子超结构
DOI：
10.1021/jp1055599
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Yadong Yin
中科院分区：
文献类型：
--
作者：
S. Zorba;Randolph Thomas Maxwell;Constantine Farah;Le He;Miaomiao Ye;Yadong Yin
我们通过实验证明了超顺磁性磁铁矿纳米粒子和磁铁矿−二氧化钛豆荚超结构用于激光强度调制和斩波的概念。调制的频率是驱动信号的两倍，并且是颗粒大小的函数。具体地说，将尺寸为86、140和190 nm的圆形纳米粒子的光调制与长度约为1μm的磁铁矿TiO2Peapod超结构的光调制进行了比较。前者产生的调制频率高达2μ，与商业光学斩波器的调制数量相当，后者高达100赫兹。我们还发现，颗粒形状的不对称性和各向异性增强了光学调制，并且调制频率与所用颗粒的惯性成反比。
We experimentally demonstrate proof of concept operation of superparamagnetic magnetite nanoparticles and magnetite−TiO2 peapod superstructures for laser intensity modulation and chopping. The frequency of the modulation is shown to be twice that of the driving signal and a function of the size of the particles. Specifically, optical modulation with round nanoparticles of sizes 86, 140, and 190 nm is compared with optical modulation with magnetite−TiO2 peapod superstructures of lengths of around 1 μm. The former gave rise to modulations of up to 2 kHz in frequency, a number comparable to that of commercial optical choppers, the latter up to 100 Hz. We also show that particle shape asymmetry and anisotropy enhance optical modulation and that modulation frequency is inversely proportional to the inertia of the particles used.