Detection of Carbonated Beverages using a PCF SPR Sensor

A Photonic Crystal Fiber (PCF) Surface Plasmon Resonance (SPR) sensor has been proposed in this work. The sensor is designed for detecting the refractive index of carbonated beverages, such as Coca-Cola, Pepsi, 7UP, Sprite, Fanta, Mountain Dew, beer, stout, Canada Dry, and Schweppes. These beverages are widely consumed for their effervescence and refreshing taste. Ensuring their quality is crucial due to variations in alcohol content, sugar content, water mixture, aging process, and additional ingredients. The sensor, designed with a circular gold layer coating over a PCF with a symmetrical structure, facilitates the SPR phenomenon. Numerical exploration using the finite element method revealed a maximum amplitude sensitivity of 787 RIU<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup>and a maximum wavelength sensitivity of 33,333.3 nm/RIU, with a wavelength sensitivity resolution of 3 × 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−6</sup>RIU and a high figure of merit of 555.56 RIU<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup>, confirming the sensor's superior performance. Demonstrating exceptional sensitivity, the sensor offers a costeffective and time-saving alternative to existing methods, also applicable in security settings such as airports and border checkpoints for detecting illegal substances. This study highlights the sensor's potential in ensuring the quality of carbonate beverages by providing valuable insights into their composition and authenticity, as well as enhancing security measures against illegal drug supply.