Analysis for an Improved Nanomechanical Microcantilever Sensor on Optical Waveguides

An analysis model for an optical waveguide microcantilever sensor is developed combining the optical and mechanical models. An improved optical waveguide microcantilever sensor with a buffer is provided and taken as an example to explore using the analysis model. A systematic and detailed discussion about the couplers for the input waveguide to optical waveguide cantilever and the optical waveguide cantilever to the output waveguide of the improved waveguide cantilever sensor is presented. The sensitivity of an improved optical waveguide cantilever sensor is evaluated by analyzing the input/output waveguide, buffer, microcantilever, and gap. An improved optical waveguide microcantilever sensor by adding a buffer shows a sensitivity of $5.7\times 10^{-4}nm^{-1} $ , which is improved by 51.3%, compared with a conventional optical waveguide microcantilever sensor. The design of an optical waveguide cantilever sensor is a trade-off of different design parameters. These will be helpful for the study of an optical waveguide cantilever sensor.