Abnormal frequency characteristics of wrinkled graphene

This paper observes an abnormal phenomenon in the frequency variation of wrinkled graphene. Compared with the pristine case, a slight wrinkle decreases the resonant frequency, while a heavy wrinkle increases the resonant frequency. This observation gave us the idea to tune the wrinkle and work out the frequency variation of graphene. Our results reveal that the frequency shift of graphene may be tuned by wrinkles ranging from 83.8% to 128.6%. The abnormal frequency variation is close to the dominant contributions of the effective mass involved in vibration and the wrinkled stress level. The effective mass involved in vibration governs the decreasing trend of the resonant frequency in graphene which has slight wrinkles. The wrinkled stress level controls the increase in resonant frequency of heavily wrinkled graphene. A modified prediction model is proposed which predicts the abnormal frequency variation and evaluates the resonant frequency of wrinkled graphene within 2% mean difference. Our results will benefit the design of wrinkle-tuned variable-frequency nano-resonators or devices.