Suspended particle devices (SPDs) adapted for controlling the transmission of electromagnetic radiation have become an area of considerable focus for smart window technology due to their desirable properties, such as instant and precise light control and cost-effectiveness. Here, we demonstrate a SPD with tunable transparency in the visible regime using colloidal assemblies of nanoparticles. The observed transparency using ZnS/SiO₂ core/shell colloidal nanoparticles is dynamically tunable in response to an external electric field with increased transparency when applied voltage increases. The observed transparency change is attributed to structural ordering of nanoparticle assemblies and thereby modifies the photonic band structures, as confirmed by the finite-difference time-domain simulations of Maxwell’s equations. The transparency of the device can also be manipulated by changing the particle size and the device thickness. In addition to transparency, structural colorations and their dynamic tunability are demonstrated using α-Fe₂O₃/SiO₂ core/shell nanomaterials, resulting from the combination of inherent optical properties of α-Fe₂O₃/SiO₂ nanomaterials and coloration due to their tunable structural particle assemblies in response to electric stimuli.

中文翻译：

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使用胶体核/壳纳米粒子可调节透明度的电光设备

适于控制电磁辐射传输的悬浮粒子设备（SPD）由于其理想的特性，例如即时和精确的光控制以及成本效益，已经成为智能车窗技术的重点关注领域。在这里，我们演示了使用纳米粒子的胶体组件在可见光范围内具有可调透明度的SPD。使用ZnS / SiO ₂观察到的透明性当施加的电压增加时，核/壳胶体纳米颗粒可动态响应外部电场而具有透明性。观察到的透明度变化归因于纳米粒子组件的结构排序，从而修改了光子能带结构，这已经通过麦克斯韦方程的时域有限差分模拟得到了证实。装置的透明度也可以通过改变粒径和装置厚度来控制。除了透明度，结构和着色它们的动态可调谐性是使用表现出的α-Fe ₂ ö ₃ /二氧化硅₂核/壳纳米材料，从固有的光学特性的组合产生的α-Fe ₂ ö ₃/ SiO ₂纳米材料及其着色是由于其对电刺激的可调谐结构粒子组装。