Theoretical verification of photonic crystals sensor for biodiesel detection and sensing

Abstract

Among the two past decades, the biodiesel fuels received a significant attention due to its lower hydrocarbon emissions and low sulfur diesel. However, the incomplete transesterification represents the main problem for the possibility of wider use. Thus, we present in this research a new method for detecting and measuring of methyl ester biodiesel fuel based on its optical characteristics. The proposed sensor is designed using the well-known one dimensional photonic crystals. The cornerstone of our idea is mainly based on two sides. First, the inclusion of methyl ester as a defect layer inside the one dimensional photonic crystals gives rise to the formation of a resonant peak within the photonic band gap. Second, the concentration of the converted methyl ester due to the transesterification reaction of soybean oil is closely related to its refractive index. Therefore, the sensing and detection procedure is essentially based on the dependence of the characteristics of the resonant peak on the concentration of the biodiesel fuel. The parameters that refer to the performance of our sensor such as, the sensitivity, figure of merit and the detection limit are investigated. Moreover, the effect of the defect layer thickness and the angle of incidence on the performance of our sensor is demonstrated. The numerical results show that our design could provide high sensitivity of 136 nm RIU−1 and figure of merit 2240 RIU–1. In addition to that, it could differentiate between the different biodiesel fuels despite the very limited difference between their indices of refraction.

One-Dimensional Phononic Crystals: A Simplified Platform for Effective Detection of Heavy Metals in Water with High Sensitivity

“…Finally, another performance parameter (i.e., the damping rate) was also considered. The damping, which defines how the acoustic waves in the designed PnCs decay following a disturbance across the structure, determines the sharpness of the resonance-transmitted peaks [ 42 , 43 , 44 , 45 ]: …”

Detection of isoprene traces in exhaled breath by using photonic crystals as a biomarker for chronic liver fibrosis disease

“…The bandgap is characterized by nearly zero transmission of EM waves. Such a wide bandgap is due to the high mismatch in refractive index between GaN and SiO 2 materials, and it is resulted due to the destructive interference of EM waves at layers boundaries [13,15]. The production of wide band gaps in the refection spectrum of PCs is considered a desired indicator for designing sensor platforms.…”

“…In other words, the insertion of a metallic layer leads to the increment of the absorption intensity of the EM waves through the PC structure [23]. The reflection intensity, bandwidth, and wavelength value of TP mode are greatly affected with any little change in the parameters of the adjacent layer (air cavity) [15,16]. This is the principle of the design isoprene senor.…”

“…The propagation of EM waves through periodic structures is manipulated by using the transfer matrix method (TMM) [15]. TMM is considered an accurate method in studying and manipulating the propagation of various types of waves through the 1D periodic lattices [15][16][17]. The TMM is completely dependent on Maxwell's equations and their solution through each layer (j) or repeated unit cells of the lattice constant (a).…”

“…Optical biosensors are characterized by high performance, inexpensive, and compact design which can be inserted with a lab-on-a-chip device [12,13]. Photonic crystals (PCs) are considered fascinating optical sensors and biosensors in recent years [14][15][16]. PCs are periodic structures in 1D, 2D, or 3D designs that able to control the propagation of electromagnetic waves (E.M waves) within ranges of frequencies called photonic band gaps (PnBG).…”