Spider silk biological material for Q-switched temperature sensor

Abstract

Abstract A temperature sensor using compact design and highly sensitivity of side polished fiber and fiber Bragg grating as the sensing elements, Q-switched pulse fiber laser source with spider silk as a saturable absorber is proposed and demonstrated. Spider silk sample was gently collected from a live spider, specifically, the jumping spider of Plexippus sp. which then incorporated within the laser cavity by deposited the silk onto the surface of the fiber ferrule to facilitate the generation of Q-switched pulse fiber laser. The temperature variations were detected by monitoring the pulse train and radio frequency shift from the oscilloscope. The performance of the side polished fiber sensor probe shows a sensitivity of 0.1522 kHz/°C, with 0.9479 coefficient of determination value as the temperature increased from −0.5 °C to +3.1 °C. Besides, a linear temperature response in the range of 25 °C–55 °C with a sensitivity of 0.0423 kHz/°C, and a linear correlation coefficient of 0.951 was experimentally achieved for a fiber Bragg grating device. The spider silk as a saturable absorber material is compatible with fiber optic interconnection and the temperature sensing characteristics were successfully demonstrated. The sensor’s straightforward design further enhances its desirability as a sensor for temperature monitoring, including in the field of biological treatments, consumer electronics, detection of chemical analytes, and medical diagnosis.