Ultrasensitive Optical Temperature Transducers Based on Surface Plasmon Resonance Enhanced Composited Goos-Hänchen and Imbert-Fedorov Shifts

The spatial and angular Goos-Hanchen and Imbert-Fedorov shifts occur simultaneously for the light beam reflected from a lossy surface (e.g., metal surface). The mixture of spatial and angular Goos-Hanchen (Imbert-Fedorov) shifts, referred to as composited Goos-Hanchen (Imbert-Fedorov) shift, has been experimentally confirmed in recent years. The temperature-dependent composite Goos-Hanchen and Imbert-Fedorov shifts for a light beam reflected from the prism-gold interface in the Kretschmann-Raether configuration are theoretically investigated. The spatial and angular Goos-Hanchen and Imbert-Fedorov shitfs of $p$ -polarized incident light are significantly enhanced around the resonant angle with the generation of surface plasmon resonance. The ultrahigh temperature sensitivities of 0.79 cm/K and 188  $\mu$ m/K are obtained with the composite Goos-Hanchen and Imbert-Fedorov shift, respectively, which are about 5 orders higher than those obtained with a bare gold surface. The ultrahigh temperature sensitivity is mostly contributed by the angular shift effect. Our results demonstrated the importance of angular shift effect in achieving an ultrahigh sensitivity. This work can serve as a guidance for the design of temperature sensor, chemical sensor and biosensor based on composite Goos-Hanchen and Imbert-Fedorov shifts.