Enhanced mass sensitivity in novel magnetoelastic resonators geometries for advanced detection systems

Abstract

Acoustic wave based sensors have a major impact in the detection of low concentration of biological and chemical agents. Magnetoelastic resonator platforms are particularly interesting due to their low cost and wireless detection process. However, efforts in improving their performance are still focused only in the reduction of the size. In the present study, a new way to increase the sensitivity of magnetoelastic sensor platforms is proposed. This work demonstrates, both theoretically and experimentally, that the mass load sensitivity can be improved by tailoring sensor geometry and mass load position. Triangular and arched triangular shapes have been tested and compared with the traditional rectangular ones. It has been observed an increase in the mass sensitivity of more than 400% in Metglas (R) 2826MB magnetoelastic sensor by using new sensor platform geometries. Even higher sensitivities have been obtained by doing partial coatings on the sensor edge/tip instead of the traditional complete uniform coating. New geometries present an increase up to 6400% in partial coatings. The obtained results clearly show the key role of magnetoelastic resonator platforms geometries in the increase of mass load sensitivity and their importance in the draw of future labor-free and wireless sensors for low mass detection systems.