All-Fiber Light Intensity Detector Based on an Ionic-Liquid-Adorned Microstructured Optical Fiber
A compact optical fiber light intensity detector based on an ionic-liquid-adorned microstructured optical fiber (MOF) is proposed. The light intensity detector is implemented by splicing an index-guiding MOF with two air holes in the innermost layer infused with ionic liquid (IL) between two segments of single-mode fibers. The transmission spectral characteristics of the proposed intensity detector under different power densities have been investigated from experimental as well as theoretical perspectives. Owing to modal interference effect and intrinsic absorption of the IL, the power density sensitivity reaches 1.5291 dB/(mW•mm–2) within a relatively linear range. The high sensitivity and feasibility of our proposed intensity detector is anticipated to serve as the key element, such as optical switch, in future all-optical networks.