论文标题
可调石墨烯语音晶体
Tunable graphene phononic crystal
论文作者
论文摘要
在语音领域，周期性模式控制振动，从而在物质中的热量和声音流动。在此类声音晶体中产生的带镜会实现低衰减振动模式，并为机械量子台，有效的波导和最先进的传感提供应用。在这里，我们结合了语音和二维材料，并探索通过施加的机械压力操纵音调晶体的可能性。为此，我们从单层石墨烯制造了最薄的可能的语音晶体，并模拟了其振动特性。我们在MHz制度中找到了一个带gap，在该制度中，我们将有效质量为0.72 ag = 0.002 $ m_ {ybolythy} $的缺陷模式定位。最后，我们利用石墨烯的柔韧性并机械调整有限尺寸的音调晶体。在高达30 kPa的静电压力下，我们观察到整个语音系统的频率高于350％以上。同时，缺陷模式停留在带隙内，并保持本地化，这表明具有高质量的动态调谐机械系统。
In the field of phononics, periodic patterning controls vibrations and thereby the flow of heat and sound in matter. Bandgaps arising in such phononic crystals realize low-dissipation vibrational modes and enable applications towards mechanical qubits, efficient waveguides, and state-of-the-art sensing. Here, we combine phononics and two-dimensional materials and explore the possibility of manipulating phononic crystals via applied mechanical pressure. To this end, we fabricate the thinnest possible phononic crystal from monolayer graphene and simulate its vibrational properties. We find a bandgap in the MHz regime, within which we localize a defect mode with a small effective mass of 0.72 ag = 0.002 $m_{physical}$. Finally, we take advantage of graphene's flexibility and mechanically tune a finite size phononic crystal. Under electrostatic pressure up to 30 kPa, we observe an upshift in frequency of the entire phononic system by more than 350%. At the same time, the defect mode stays within the bandgap and remains localized, suggesting a high-quality, dynamically tunable mechanical system.
