Vibration analysis of nanomechanical mass sensor based on circular graphene sheets

Graphene sheet (GS) is a two-dimensional (2D) material with extremely favorable mass sensor properties. In this paper, a linear elastic 2D plate model is applied to study the potential of a nanoscale mass sensor on individual GS. The simulated natural frequency was compared with the results obtained from the Rayleigh´s energy method. The effects of the attached mass, aspect ratio, and the layer number of the GS on the natural frequency are investigated in detail. Initial tension due to the fabrication process and temperature is also studied, which has effects on the frequency and frequency shift. The results show that the sensitivity of the mass sensor with smaller dimension is higher. The resolution of mass sensor can reach 1 zg and the sensitivity of seven-layer graphene mass sensor is the highest. Lower temperature has higher sensitivity and initial tension due to the fabrication process has little influence on the mass sensor. The conclusion is useful for the design of mass sensor with high resolution.