Photothermal Effect in Plasmonic Nanotip for LSPR Sensing. The influence of heat generation on the conventional process of LSPR based sensing has not been explored thus far. Therefore, a need exists to draw attention toward the heat generation issue during LSPR sensing as it may affect the refractive index of the analyte, leading to incorrect sensory conclusions. This manuscript addresses the connection between the photothermal effect and LSPR. We numerically analyzed the heat performance of a gold cladded nanotip. The numerical results predict a change in the microscale temperature in the microenvironment near the nanotip. These numerical results predict a temperature increase of more than 20 K near the apex of the nanotip, which depends on numerous factors including the input optical power and the diameter of the fiber. We analytically show that this change in the temperature influences a change in the refractive index of the microenvironment in the vicinity of the nanotip. In accordance with our numerical and analytical findings, we experimentally show an LSPR shift induced by a change in the input power of the source. We believe that our work will bring the importance of temperature dependence in nanotip based LSPR sensing to the fore.

Enhancing Temperature Sensitivity of the Fabryxe2x80x93Perot Interferometer Sensor with Optimization of the Coating Thickness of Polystyrene The exploration of novel polymers for temperature sensing with high sensitivity has attracted tremendous research interest. Hence, we report a polystyrenecoated optical fiber temperature sensor with high sensitivity. To enhance the temperature sensitivity, flat, thin, smooth, and air bubblefree polystyrene was coated on the edge surface of a singlemode optical fiber, where the coating thickness was varied based on the solution concentration. Three thicknesses of the polystyrene layer were obtained as 2.0, 4.1, and 8.0 xcexbcm. The temperature sensor with 2.0 xcexbcm thick polystyrene exhibited the highest temperature sensitivity of 439.89 pm xc2xb0Cxe2x88x921 in the temperature range of 25xe2x80x93100 xc2xb0C. This could be attributed to the very uniform and thin coating of polystyrene, along with the reasonable coefficient of thermal expansion and thermooptic coefficient of polystyrene. Overall, the experimental results proved the effectiveness of the proposed polystyrenecoated temperature sensor for accurate temperature measurement.