Influence of surface micro-beams with large deflection on the resonance frequency of a quartz crystal resonator in thickness-shear mode vibrations

We study the dynamic behavior of a quartz crystal resonator （QCR） in thickness-shear vibrations with the upper surface covered by an array of micro-beams （MBs） under large deflection. Through taking into account the continuous conditions of shear force and bending moment at the interface of MBs/resonator, dependences of frequency shift of the compound QCR system versus material parameter and geometrical parameter are illustrated in detail for nonlinear and linear vibrations. It is found that the frequency shift produces a little right （left） translation for increasing elastic modulus （length/radius ratio） of MBs. Moreover, the frequency right （left） translation distance caused by nonlinear deformation becomes more serious in the second-order mode than in the first-order one,

A novel sensitive piezoelectric mass balance used for weightless environment

A novel sensitive piezoelectric mass balance(PEMB)was developed for using in weightless environment.The mass of the measured object was obtained by detecting the resonant frequency shift of the PEMB.This weighing method was illustrated systematically.In order to build the relationship between the resonant frequency shift and the measured mass,the equivalent stiffness coefficient and the equivalent concentrated mass of the PEMB were analyzed theoretically.The influence of the structural and material parameters on the sensitivity was analyzed,which provided the design reference to improve the sensitivity.The finite-element-method(FEM)static analysis of the PEMB was carried out with ANSYS software to investigate its shock resistance.Furthermore,the vibration test and calibration experiment effectively verified the theoretical analyses results.The developed PEMB holds merits of independence on acceleration field,independence on properties of the measured object and with shock resistance.Consequently,it can be a suitable candidate for measuring mass of solid samples with unknown properties in the weightless environment.

Incident Light Influence on the Transmission of Coupled Ring Resonators

The transmission matrix method is used to analyze the influence of incident light on coupled resonators. Two different types of incident light on the same coupled resonator geometry are shown to lead to different system transmission features. The EIT-like phenomenon occurs in the type I case with the transmission being symmetric around the zero-single-pass-phase-shift frequency. In the type Ⅱcase the resonant frequency has a blue shift corresponding to the increasing coupling strength between the two ring resonators. Also, the critical-coupling-like condition exists in the type Ⅱconfiguration to maintain the zero-single pass-phase-shift frequency. The incident light, as well as the geometry, partially determine the mode interference in the coupled ring resonator system.