title: Optical temperature sensor with enhanced sensitivity by employing hybrid waveguides in a silicon Mach-Zehnder interferometer.
abstract: We report on a novel design of an on-chip optical temperature sensor based on a Mach-Zehnder interferometer configuration where the two arms consist of hybrid waveguides providing opposite temperature-dependent phase changes to enhance the temperature sensitivity of the sensor. The sensitivity of the fabricated sensor with silicon/polymer hybrid waveguides is measured to be 172 pm/°C, which is two times larger than a conventional all-silicon optical temperature sensor (~80 pm/°C). Moreover, a design with silicon/titanium dioxide hybrid waveguides is by calculation expected to have a sensitivity as high as 775 pm/°C. The proposed design is found to be design-flexible and robust to fabrication errors.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Guan
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Wang
authors.forename: Lars H
authors.initials: LH
authors.lastname: Frandsen