ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels (Barcelona) 08860, Spain.
Nat Commun. 2016 Aug 9;7:12496. doi: 10.1038/ncomms12496.
Mechanical resonators based on low-dimensional materials are promising for force and mass sensing experiments. The force sensitivity in these ultra-light resonators is often limited by the imprecision in the measurement of the vibrations, the fluctuations of the mechanical resonant frequency and the heating induced by the measurement. Here, we strongly couple multilayer graphene resonators to superconducting cavities in order to achieve a displacement sensitivity of 1.3 fm Hz(-1/2). This coupling also allows us to damp the resonator to an average phonon occupation of 7.2. Our best force sensitivity, 390 zN Hz(-1/2) with a bandwidth of 200 Hz, is achieved by balancing measurement imprecision, optomechanical damping, and measurement-induced heating. Our results hold promise for studying the quantum capacitance of graphene, its magnetization, and the electron and nuclear spins of molecules adsorbed on its surface.
基于低维材料的机械谐振器在力和质量传感实验中很有前景。这些超轻谐振器的力灵敏度通常受到振动测量不精确、机械谐振频率波动以及测量引起的加热的限制。在这里，我们将多层石墨烯谐振器与超导腔强烈耦合，以实现 1.3 fm Hz(-1/2)的位移灵敏度。这种耦合还允许我们将谐振器阻尼到平均声子占据数为 7.2。通过平衡测量不精确、光机械阻尼和测量引起的加热，我们获得了最佳的力灵敏度 390 zN Hz(-1/2)，带宽为 200 Hz。我们的结果有望用于研究石墨烯的量子电容、其磁化以及吸附在其表面上的分子的电子和核自旋。
