Suspended Ring-Core Photonic Crystal Fiber Gas Sensor With High Sensitivity and Fast Response

Abstract

We demonstrate the design and fabrication of an in-line evanescent field gas sensor based on a novel suspended ring-core photonic crystal fiber (PCF) to further overcome limitations in sensing capability. The suspended ring-core PCF is made by the stack-and-draw technique with a large central capillary of $ 60 m and adapted small capillaries in a larger cladding tube. Sensing capabilities of two variations of the proposed suspended ring-core PCFs were investigated experimentally by detecting absorption lines of acetylene gas. The sensitivity of the two PCF structures was also numerically analyzed using a full-vectorial finite-element method. The dynamic response of the sensors was quantified in detail. The results demonstrated significant improvement in both sensitivity and response time of the suspended ring-core PCF as this special PCF can provide larger gas diffusion and higher overlap between the sensing species and the guided light than either a Ge-doped ring defect PCF or a conventional index-guided PCF.

Design and optimization of photonic crystal fiber based sensor for gas condensate and air pollution monitoring

“…Nowadays, gas sensing capability of PCF is enhanced rapidly due to its several attractive features like the high relative sensitivity and low confinement loss. The performances of gas sensors are enlarged by changing the size or number of air cavities [26]. The global warming problem is very acute day by day due to various types of toxic gases including C 2 H 2 , CH 4 , NO 2 , SO 2 , NH 3 , H 2 S, CO 2 , and CO.…”

[INVITED] New perspectives in photonic crystal fibre sensors

“…The holey structure of PCFs offers an additional degree of freedom in the design of optical sensors as they can be infiltrated with liquids, gases or nanomaterials [16][17][18][19][20][21][22][23]. In most cases the PCF plays also the role of gas or liquid chamber.…”

“…This gives rise to a strong light-matter interaction, hence to high sensitivity. The complexity of the setups to infiltrate gases, liquids or nanoscale materials in the PCFs [16][17][18][19][20][21][22][23] is an issue that must be minimised otherwise it will be difficult to find practical applications of PCFs for gas or liquid sensing. On this regard, PCF sensors can benefit from the advances in micro-and opto-fluidics and nanotechnology.…”

In-line chemical sensor based on C-type fiber and novel photonic crystal fibers with high sensitivity and fast dynamic response

“…However, improving the sensing sensitivity and response time is still an on-going critical issue. In recent years, micro-structured optical fibers, especially photonic crystal fibers (PCFs), have attracted considerable interests for sensing applications due to the fact that micro-holes in PCFs can provide a strong and long interaction between the guided light and gases or liquids filled within the holes of PCFs [7]. In PCF-based sensor, however, the rate of gas diffusion into the micron-sized holes caused various limitations in sensing capability [8].…”