Liquid Concentration Sensing Properties of Microfibers with a Nanoscale-Structured Film

• Published in: Chinese physics letters Vol. 32; no. 3; pp. 45 - 48
• Main Author: 周国瑞 吕海兵 袁晓东 周海 刘昊 李可欣 程晓锋 苗心向
• Format: Journal Article
• Language: English
• Published: Chinese Physical Society and IOP Publishing 01.03.2015
• Subjects: Detection; Finite difference method; Liquids; Mathematical analysis; Microfibers; Nanostructure; Optical properties; Sensors; 传感特性; 微纤维; 有限差分时域; 浓度传感器; 液体浓度; 纳米结构薄膜; 结构化; 超细纤维
• ISSN: 0256-307X; 1741-3540
• DOI: 10.1088/0256-307X/32/3/034202

A type of compact solution concentration sensor based on a microfiber with a nanoscale-structured film is proposed and demonstrated experimentally. Additional loss at different solution concentrations is calculated by means of the three-dimensional finite-difference time-domain （3D-FDTD） method. The microfiber is fabricated by using the flame-heated scanning technique. Nanoscale-structured film is coated on the microfiber surface, which is assembled as a sensing unit. The sensitivity of this kind of sensor increases with the decreasing diameters of the microfiber. When the diameter of the microfiber is 2 #m, a minimum concentration sensitivity of 1% （under 450s measuring time） is demonstrated in the experiment. Higher sensitivity can be attained when the solution concentration is higher. The sensing properties of this microfiber with the nanoscale-structured film may provide opportunities for new applications in optical sensing devices.