Numerical Study of Fabrication-Related Effects of the Structural-Profile on the Performance of a Dielectric Photonic Crystal-Based Fluid Sensor

Abstract

In this work, fabrication of a dielectric photonic crystal device and numerical study of its spectral characteristics as a refractive index sensor are presented for near infrared range. The proposed nanosensor device is composed of low-cost dielectric materials, i.e., silicon dioxide and niobium pentoxide, and is fabricated using focused ion-beam milling lithography. In the first part, the fabrication process of the device is discussed, along with the process parameters and their effects on the structural properties of the resulting photonic crystal elements. In the second part, the device is numerically tested as a sensor for the biological refractive index range of 1.33 to 1.4. The performance considerations of the biosensor device are studied for 12 different structural profiles based on the fabrication results. It is shown that the angular-wall-profile of the fabricated structures downgrades the performance of the sensor, and the optimum value of hole depth should be in the range of 930–1500 nm to get the best performance. A sensitivity of 185.117 nm/RIU and a figure of merit of 9.7 were recorded for the optimum design of the device; however, a maximum sensitivity of 296.183 nm/RIU and a figure-of-merit of 13.184 RIU−1 were achieved. The device is recommended for a variety of biosensing applications due to its inert material properties, stable design and easy integration with fiber-optic setups.

A 3-Dimensional Modelling of the Optical Switch Based on Guided Mode Resonances in Photonic Crystals

“…Therefore, during execution the desired arrangement is transformed initially into a finitearrangement of grids known as the YEE grids [60], to compute the Electric 'E' field and Magnetic 'B' field based on Maxwell's equations. Moreover, FDTD is advantageous in terms of computing the response of the system in a single run (using a short Gaussian pulse), providing the user with the propagation of the wave both in near-field and far-field especially inside complex structures like PhCs [61]. Apart from these, requires fewer-computational resources, memory, and time as related to frequency domain-based simulations [62].…”

A Novel Design of Optical Switch Based on Guided Mode Resonances in Dielectric Photonic Crystal Structures

“…During GMR, the free-space modes in the incident light interfere with the leaks modes and the guided modes inside the structures using phase matching mechanism to create resonances. PhCs are capable of guiding and manuplating the light at wavelength scale [13] and their usage has been reported in various optical filtering [14] and sensing [15,16] applications. This work presents a novel idea to implement optical switching action using optical amplification in PhC structures by enabling interference of in-plane index-guided modes and out-of-the-plane coupled resonances.…”

Thermal Sensor Based on Polydimethylsiloxane Polymer Deposited on Low-Index-Contrast Dielectric Photonic Crystal Structure

“…Due to the sensitive nature of these Fano-resonances, they have been widely used in sensing applications [3]. Optical sensing has recently been an attractive topic of research with its application areas, including fluid sensing [4], gas sensing [5,6] biomedical sensing [7,8], and thermal sensing [7][8][9]. Moreover, the resonance conditions can also be altered by changing the refractive index of the adjacent medium to the PhC structure in the sensor device.…”

“…Two-dimensional PhCs have widely been reported for sensing applications, including temperature sensing [7][8][9][14][15][16][17], biomedical sensing [7,18,19], bacteria sensing [20][21][22], fluid sensing [4], gas sensing [5,6] and refractive index sensing in general [23][24][25][26]. Refractive index sensing using perfect absorbers for electromagnetic waves in the ultraviolet spectral range has been presented in [26][27][28][29].…”

“…Recently, optical-fiber-based refractive index sensing has also been suggested in many research works [9,15,16,25,30]. Optical temperature sensing has been reported using various techniques, such as index sensing [3,6,14], perfect absorbers [7], plasmonic sensors [5,8,9,14,17], Fano-resonance-based sensors [4,31], fiber-optic-based sensing [9,15,16,30], and nanocavity-based sensing [8]. Thermal sensing has also been demonstrated using plasmonic waveguides in combination with thermally sensitive media, such as ethanol and PDMS [31][32][33].…”