论文标题
在低压力纳米力学二氮气中，局部模式的热传输和频率响应，具有声音带隙结构
Thermal transport and frequency response of localized modes on low-stress nanomechanical silicon nitride drums featuring a phononic bandgap structure
论文作者
论文摘要
开发宽带热传感器，用于检测辐射，单纳米颗粒或单个分子的开发。近年来，已经成功证明了基于应力纳米力学谐振器的共振频率的变化光热光谱。在这里，我们显示了由氮化硅作为热传感器制成的软钳制的语音晶体膜的应用。与有限元方法模拟一致，在实验上证明了准带gap如何保持在非常低的拉伸应力。与均匀大小相等的平方膜相比，发现基本缺陷模式的相对响应性的提高，其增强因子与数量级一样大。然后，我们显示了在纳米力学蹦床内部设计的语音晶体，从而导致拉伸应力增加并增加热分离，从而进一步增强了响应性。最后，通过激光加热缺陷到基本缺陷模式完全离开带隙的点显示缺陷模式和带隙调整。
Development of broadband thermal sensors for the detection of, among others, radiation, single nanoparticles, or single molecules is of great interest. In recent years, photothermal spectroscopy based on the shift of the resonance frequency of stressed nanomechanical resonators has been successfully demonstrated. Here, we show the application of soft-clamped phononic crystal membranes made of silicon nitride as thermal sensors. It is experimentally demonstrated how a quasi-bandgap remains even at very low tensile stress, in agreement with finite element method simulations. An increase of the relative responsivity of the fundamental defect mode is found when compared to that of uniform square membranes of equal size, with enhancement factors as large as an order of magnitude. We then show phononic crystals engineered inside nanomechanical trampolines, which results in additional reduction of the tensile stress and increased thermal isolation, resulting in further enhancement of the responsivity. Finally, defect mode and bandgap tuning is shown by laser heating of the defect to the point where the fundamental defect mode completely leaves the bandgap.
