Ultrasensitive Micro-/Nano-Fiber-Enabled Flexible Sensor for Monitoring Human Temperature

Future wearable devices for health monitoring require sensitive and efficient monitoring systems. Here, we propose an optical fiber wearable sensor based on the Vernier effect and structural design sensitization. The cascaded dual micro-/nano-fiber configuration forms the Vernier effect. The pre-bending structure not only increases sensitivity but also improves the tensile performance of the sensor. The wearable sensor we proposed has a significant temperature sensitivity of 6.54 nm/°C, which is several times or even tens of times higher than the sensitivity of conventional sensors. The ultrahigh sensitivity, mechanical robustness, and excellent flexibility and biocompatibility make this sensor system an advanced wearable high-precision temperature monitoring medical device. This wearable sensor overcomes the limitations of commonly reported flexible devices based on electrical, optical, and materials. It has shown advantages in detecting the average skin temperature and local temperature of the human body.