Asymmetrically coupled resonators for mass sensing

This paper presents a new design of microelectromechanical systems (MEMS) based low-g accelerometer utilizing mode-localization effect in the three degree-of-freedom (3-DoF) weakly coupled MEMS resonators. Two sets of the 3-DoF mechanically coupled resonators are used on either side of the single proof mass and difference in the amplitude ratio of two resonator sets is considered as an output metric for the input acceleration measurement. The proof mass is electrostatically coupled to the perturbation resonators and for the sensitivity and input dynamic range tuning of MEMS accelerometer, electrostatic electrodes are used with each resonator in two sets of 3-DoF coupled resonators. The MEMS accelerometer is designed considering the foundry process constraints of silicon-on-insulator multi-user MEMS processes (SOIMUMPs). The performance of the MEMS accelerometer is analyzed through finite-element-method (FEM) based simulations. The sensitivity of the MEMS accelerometer in terms of amplitude ratio difference is obtained as 10.61/g for an input acceleration range of ±2 g with thermomechanical noise based resolution of 0.22 and nonlinearity less than 0.5%.

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Active control of the hybridization effect of near-field coupled resonators in metamaterial for a tunable negative refractive index at terahertz frequencies

Journal of Physics and Chemistry of Solids ◽

10.1016/j.jpcs.2021.110173 ◽

2021 ◽

pp. 110173

Author(s):

Nguyen Thi Hien ◽

Nguyen Xuan Ca ◽

Bui Xuan Khuyen ◽

Tran Van Huynh ◽

Nguyen Sy Khiem ◽

...

Keyword(s):

Refractive Index ◽

Active Control ◽

Negative Refractive Index ◽

Near Field ◽

Coupled Resonators ◽

Hybridization Effect ◽

Terahertz Frequencies

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Nanomechanical Molecular Mass Sensing Using Suspended Microchannel Resonators

Sensors ◽

10.3390/s21103337 ◽

2021 ◽

Vol 21 (10) ◽

pp. 3337

Author(s):

Alberto Martín-Pérez ◽

Daniel Ramos ◽

Javier Tamayo ◽

Montserrat Calleja

Keyword(s):

Molecular Mass ◽

Mass Density ◽

Applied Pressure ◽

Atomic Mass ◽

Liquid Sample ◽

Mass Sensing ◽

Average Molecular Mass ◽

Fluid Properties ◽

Molecular Masses ◽

Microchannel Resonators

In this work we study the different phenomena taking place when a hydrostatic pressure is applied in the inner fluid of a suspended microchannel resonator. Additionally to pressure-induced stiffness terms, we have theoretically predicted and experimentally demonstrated that the pressure also induces mass effects which depend on both the applied pressure and the fluid properties. We have used these phenomena to characterize the frequency response of the device as a function of the fluid compressibility and molecular masses of different fluids ranging from liquids to gases. The proposed device in this work can measure the mass density of an unknown liquid sample with a resolution of 0.7 µg/mL and perform gas mixtures characterization by measuring its average molecular mass with a resolution of 0.01 atomic mass units.

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