Design of microscale plasmonic devices for temperature change sensing at visible wavelengths

摘要

Photonic devices used in photonic integrated circuits are very important to understand high performance devices. To increase reliability of these devices, temperature characteristics of these devices need to be investigated. Still, no device that can simply sense temperature change in microscale exists. Hence, we have designed microscale plasmonic devices for temperature change sensing at the wavelength of near 633 nm. The designed device consists of a single- and a multimode plasmonic channel waveguide with two different trench depths. The designed device utilizes multimode interference of channel plasmon polaritons for sensing temperature change. The designed device can be applied in the range of the temperature change that silver coefficient of thermal expansion does not greatly change, such as the temperature from room temperature to +/- 30 degrees C. The temperature change sensitivity of the designed device has been numerically confirmed by the finite-difference time-domain method. The temperature change sensitivity of the designed device is a little inferior to that of existing temperature sensing devices. However, the designed device can be realized under one hundredth of the size of existing temperature change sensing devices. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)