D-shaped Photonic Crystal Fiber Research Articles

A Multi-Plasmonic Approach for Simultaneous Measurements based on a D-Shaped Photonic Crystal Fiber Sensor: from Temperature to Optical Dispersion

The growing demand for multiparameter sensors includes compact devices accompanied by simple calibration processes to distinguish the outputs from each other. This paper evaluates a scheme to determine multiple parameters of a medium using localized surface plasmon resonances (SPR) excited on a Dshaped photonic crystal fiber (PCF) partially covered by two gold layers of different thicknesses. We demonstrate that the proposed sensing platform, once customized to characterize the possible dispersive profiles of the refractive index of the analyte, also allows interrogating the temperature of a sample from a linear relationship. Since the plasmonic resonances are excited at separated and low crosstalk spectral channels, different sensing responses can be obtained simultaneously in the same location of the D-shaped PCF. These features turn out the SPR sensor a suitable tool for simultaneous monitoring of optical dispersion and temperature.

Dual-band highly-sensitive SPR photonic crystal fiber sensor based on birefringence analysis

In this paper, a dual-band highly-sensitive D-shaped photonic crystal fiber (PCF) sensor based on surface plasmon resonance (SPR) is proposed and numerically analyzed. Au-TiO2 grating is deposited on the flat surface of D-shaped PCF, thus surface plasmon resonances are excited to detect the change of refractive index (RI) of analyte. Rabi-like splitting spectrum is achieved by the introduction of a small air hole in the fiber. Besides spectrum analysis, it is found that the resonance wavelengths can be located by the abnormal change of birefringence. Moreover, complete coupling and incomplete coupling of the guided mode and plasmonic mode can be distinguished from our simulation results. The influences of structural parameters are also analyzed systematically. Simulation results show that the two loss peaks have different RI detection ranges, and the maximum sensitivity reaches 26700 nm/RIU. The proposed sensor could be applied widely in biomedical and chemical fields.

Design of Plasmonic Infrared Sensor Based on D-Shaped Photonic Crystal Fiber with Au-TiO2 Coating Grooves

Design of Plasmonic Infrared Sensor Based on D-Shaped Photonic Crystal Fiber with Au-TiO2 Coating Grooves

Simulation of High-Performance Surface Plasmon Resonance Sensor Based on D-Shaped Dual Channel Photonic Crystal Fiber for Temperature Sensing.

This paper presents and numerically analyzes a refractive index sensor based on side-polished D-shaped two-channel photonic crystal fiber (PCF) and surface plasmon resonance (SPR). The effects of pore duty ratio, polishing depth, and thickness of a Nano-Titania sensitizing layer on sensor performance are studied, and the sensor performance is analyzed and optimized. The results show that the sensitivity of the Nano-Titania sensitized sensor can reach 3392.86 nm/RIU and temperature sensitivity of the sensor is increased to 1.320 nm/K, and the amplitude sensitivity of the unsensitized sensor can reach 376.76 RIU-1. In addition, the influence of titanium dioxide layer on the mode field diameter of PCF fiber core is also studied. It is found out that the sensor with a 50 nm thick titanium dioxide film has a larger mode fiber diameter, and is more conducive to coupling with single-mode fiber. Our detailed results contribute to the understanding of SPR phenomena in hexagonal PCF and facilitate the implementation and application of SPR-PCF sensors.

MXene (Ti3C2Tx) coated highly-sensitive D-shaped photonic crystal fiber based SPR-biosensor

In this paper, a D-shaped surface plasmon resonance (SPR) refractive index (RI) based biosensor is reported for the earlier detection of various bio-analytes. The lattice of D-shaped photonic crystal fiber (PCF) offers a modified rhombus pattern for cladding air holes. D-shaped PCF is an open channel structure that fundamentally provides ease while interacting with different bio-analytes as compared to closed channels SPRs. A nanoscale MXene (Ti3C2Tx) layer is introduced with a uniform coating that drastically enhances the sensor’s sensitivity and performance. Finite element method (FEM) is employed to determine dispersion characteristics to acquire the confinement loss spectra as a function of wavelength for various bio-analytes. SPR shifts the resonant interference dip when RI of bio-analytes changes. The proposed SPR sensor with Au/ Ti3C2Tx layer exhibits maximum RI sensitivity of 47,260 nm/RIU at an analyte refractive index of 1.42 with a detection resolution of 2.11 × 10−6 RIU, which is 1.7 times higher than that of a single Au-layer SPR sensor. Moreover, it detects a wider range of bio-analytes (i.e., 1.30–1.43) using a third-order polynomial fitting function corresponding to the wavelength shift. It covers the detection of most known bio-analytes, i.e., cancerous cervical, breast and blood cells, adrenal gland, glucose concentration, proteins, viruses or DNA/RNA, etc.

Design of an Er-doped surface plasmon resonance-photonic crystal fiber to improve magnetic field sensitivity.

In order to meet the demand for large-scale magnetic field testing, this paper proposes a D-shaped magneto-refractive photonic crystal fiber (MRPCF) based on surface plasmon resonance (SPR) by using the erbium-doped materials. The four different structures of Models A, B, C, and D are designed by changing the diameter, the position, and the number of layers of the air holes, and the corresponding magnetic field sensing characteristics are analyzed. The results show that in the magnetic field range of 5-405 mT, the magnetic field sensitivities of Models A, B, C, and D are 28 pm/mT, 48 pm/mT, 36 pm/mT, and 21 pm/mT, respectively. Meanwhile, the figure of merit (FOM) of the four MRPCF-SPR sensors is investigated, which have FOMs of 4.8 × 10-4 mT-1, 6.4 × 10-4 mT-1, 1.9 × 10-4 mT-1, 0.9 × 10-4 mT-1. Model B has higher sensitivity and larger FOM. In addition, the effect of the structural parameters of Model B on the sensing performance is also studied. By optimizing each parameter, the magnetic field sensitivity of the optimized Model B is increased to 53 pm/mT, and its magneto-refractive sensitivity and FOM are 2.27 × 10-6 RIU/mT and 6.2 × 10-4 mT-1, respectively. It shows that the magneto-refractive effect of MRPCF can be effectively enhanced by optimizing the structural design of fiber. The proposed MRPCF is an all-solid-state fiber, which solves the instability problem of the magnetic fluid-filled fiber and reduces the complexity of the fabrication process. The all-solid-state MRPCF can be used in the development of quasi-distributed optical fiber magnetic field sensors and has broad applications in the fields of geological exploration, earthquake and tsunami monitoring, and military navigation.

Experimental and numerical characterization of a D-shaped PCF refractive index sensor

Highly sensitive D-shaped plasmonic photonic crystal fiber (PCF) sensor is proposed, analyzed and fabricated for refractive index (RI) sensing. The reported sensor relies on the coupling between the core guided mode and the surface plasmon mode at the metallic/dielectric interface. The resonance frequency is a function of the analyte RI within a range of 1.33–1.354. Therefore, the reported D-shaped PCF holds great potential as a highly sensitive RI sensor to detect an unknown analyte refractive index within the tested RI range. The geometrical parameters are studied to maximize the sensor sensitivity by using full vectorial finite element method. Then, the optimum design is fabricated by using stack and draw technique. The fabricated PCF sensor achieves high sensitivity of 294.11 nm/RIU with a resolution of 3.4 times 10^{ - 4} ;{text{RIU}}. The reported RI sensor can be used for glucose concentration detection where the analyte refractive index changes with the glucose concentration within the studied RI range. Hence, this design will play a significant role in the biomedical sensor industry.

Single-mode D-shaped photonic crystal fiber surface plasmon resonance sensor with open microchannel

Accessible microchannels that allow microscale fluid control and microparticle-filtering are promising tools for advanced biological and chemical sensing and analysis. To this end, we proposed a d-shaped photonic crystal fiber surface plasmon resonance sensor with open microchannel. The optical characteristics of the sensor were numerically investigated using the Finite Element Method and the fiber structure was then fabricated using a standard stack-and-draw method. The numerical results demonstrate that the d-shaped photonic crystal fiber can be applied as a sensor with wide refractive index detection range between 1.330 and 1.435, a maximum sensitivity of 28400 nm/RIU, finest resolution of 3.52 × 10−6 RIU, and maximum figure-of-merit of 592 RIU−1. The sensor operates in the single-mode regime, has good linearity range, requires simple fabrication, has high coupling efficiency with conventional single-mode fibers, and has low losses, making it a practical candidate for wide range of applications in chemical and biological testing.

Refractive index sensor based on plasmonic D-shaped photonic crystal fiber with pyramid grating

In this work, highly sensitive D-shaped photonic crystal fiber (PCF) sensor with plasmonic pyramid grating is introduced and analyzed. The sensing mechanism depends on the coupling between the fundamental core mode and the surface plasmon mode around the plasmonic pyramid grating. The resonance frequency depends on the analyte refractive index (RI) which can be employed to detect the analyte RI changes. The geometrical parameters of the proposed PCF and gold pyramid grating are studied to enhance the RI sensor sensitivity. The simulation results are obtained using full vectorial finite element method. The suggested sensor has higher sensitivity of 5200 nm/RIU than 3340 nm/RIU of the conventional grating design through the studied RI range from 1.355 to 1.385. Therefore, the reported RI sensor can be used for basal cancer cell detection with normal and cancerous cells’ refractive indices of 1.36 and 1.38, respectively. Additionally, linear performance is achieved using the reported design.

Infrared D-type photonic crystal fiber sensor for special drug detection and wide-range refractive index detection

In the field of drug inspection, the refractive indices (RIs) of many halogenated ethers and drugs are in the lower range; for example, the RI of anesthetic sevoflurane is approximately 1.27. Infrared spectral detection technology has significant advantages in the field of drug detection; to realize the RI sensing of such drugs in the infrared region, a D-shaped photonic crystal fiber sensor based surface plasmon resonance was investigated in this study. The side polishing adopted here can significantly shorten the distance between the core and metal layer, making the energy of the core easier to detect, reducing the difficulty of coating the metal layer, and improving the performance of the sensor. The structure is provided with two large-sized air holes on both sides of the fiber core, so that the sensor is suitable for sensing in the low RI range and has high wavelength sensitivity in the low RI range. The sensor works mainly in the infrared band, with a detection range of 1.20–1.34, maximum wavelength sensitivity of 24,000 nm/RIU, and resolution of 4.1667 × 10 − 6 R I U . The sensor has excellent performance and is easy to manufacture due to the simple structure; it has broad application prospects in low RI range detection fields such as biomedicine, drug detection, environmental monitoring, and water quality monitoring.

Surface plasmon resonance sensor based on the dual core D-shape photonic crystal fiber for refractive index detection in liquids

A dual-core D-shape photonic crystal fiber sensor based on surface plasmon resonance is designed and analyzed numerically by the finite element method employing the perfectly matched layer boundary conditions. The resonance peaks shift as the analyte refractive indexes are varied. An average sensitivity of 17,200 nm / RIU is achieved in the RI range between 1.40 and 1.44 and the corresponding resolution is 5.8 × 10 − 6 RIU. The various factors affecting the sensing properties are assessed and in particular, the combined effects of two variables are evaluated.

Surface plasmon resonance sensor based on D-shaped photonic crystal fiber for low refractive index detection

A D-shaped photonic crystal fiber (PCF) low refractive index (RI) sensor based on surface plasmon resonance (SPR) is proposed, and its properties are investigated by the finite element method. Gold is selected as the plasmonic material and coated on the open-ring structure to excite the plasmonic modes. The simulation results indicate that the sensor can detect the RI in the range of 1.00 to 1.29, which is a fairly wide detection range in the detection field of SPR-based PCF low RI sensors. When the analyte of the RI varies from 1.28 to 1.29, the maximum sensitivity of 10,000 nm / RIU and the corresponding resolution of 1 × 10 − 5 RIU are obtained in the wavelength range of 1.6 to 2.4 μm. When the RI of the analyte changes from 1.00 to 1.29, the relationship curve between the RI and the resonance wavelength fits well, and the adjusted R2 value is 0.99609. Furthermore, the sensor achieves the figure of merit of 56.98 RIU − 1 and an amplitude sensitivity of 82.76 RIU − 1, respectively. Therefore, the designed sensor can be effectively applied to low RI detection, having a certain commercial potential in medical detection, organic chemistry detections, and related applications.

Micro-Channel Plasmon Sensor Based on a D-Shaped Photonic Crystal Fiber for Malaria Diagnosis With Improved Performance

In this paper, a D-shaped photonic crystal fiber (PCF) sensor based on surface plasmon resonance with a micro-rectangular opening is proposed. The micro-rectangular opening introduces strong coupling between the metal layer and the core-guided mode as it helps in reducing the distance between the sensing channel and the core of the PCF. Gold (Au) is a noble plasmonic material, which is deposited on the micro-rectangular opening in order to generate an ample amount of surface plasmon on the micro-opening area’s surface. This micro opening also allows for the ease of fabrication while maintaining strong bio-detection capabilities. The obtained results as maximum wavelength sensitivity, resolution, and figure of merit are 67,000 nm/RIU, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${1.5} \times {10}^{-{6}}$ </tex-math></inline-formula> RIU and 279.16 RIU <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-{1}}$ </tex-math></inline-formula> respectively. These results indicate that they are significantly finer than those existing in the related state of the art, and that the proposed fiber sensor is easy to fabricate. Further, the proposed fiber sensor is utilized for the detection of malaria disease. The proposed sensor’s computed sensitivities for ring stage, trophozoite stage, and schizont stage RBCs of malaria disease are 25,715.30 nm/RIU, 33,157.89 nm/RIU, and 44,827.58 nm/RIU, respectively.

D-Shaped Tellurite Photonic Crystal Fiber Hydrogen and Methane Sensor Based on Four-Wave Mixing With SPR Effect

A new D-shaped tellurite photonic crystal fiber sensor based on the four-wave mixing (FWM) effect with the surface plasmon resonance (SPR) effect is designed and optimized. The substrate of the D-shaped photonic crystal fiber (D-PCF) is tellurite glass, and the polished surface is plated with the gold film and hydrogen gas-sensitive film. An air hole of the inner cladding, which is plated with the gold film and methane gas-sensitive film, is selected as the second sensing channel to simultaneously measure the concentration of hydrogen and methane. Based on the four-wave mixing, the wavelength shifts of the Stokes and anti-Stokes spectra resulting from the variation of the gas concentration can be used to accurately detect the concentrations of methane and hydrogen. Meanwhile, it is found that the SPR effect can increase the wavelength shifts, which means the sensitivity of methane and hydrogen augment. After parameter optimization, the maximum sensitivities of methane and hydrogen are 4.03 nm/% and −14.19 nm/%, respectively. Both the linearities are up to 99.9%. The resolution of methane is 1.25×10−2% and hydrogen is 7.14×10−3%. Moreover, the fiber length of this sensor is only 20 mm, which is conducive to the construction of a compact or ultra-compact embedded FWM fiber sensor.

A high sensitivity localized surface plasmon resonance sensor based on D-shaped photonic crystal fiber for low refractive index detection

A high sensitivity localized surface plasmon resonance sensor based on D-shaped photonic crystal fiber for low refractive index detection

D-Shaped Surface Plasmon Photonic Crystal Fiber Temperature Sensor

A D-shaped photonic crystal fiber (PCF) temperature sensor based on surface plasmon resonance (SPR) with high sensitivity and high figure of merit is presented in this paper. To enhance surface plasmon resonance, the gold film is deposited on the polished flat of D-shaped photonic crystal fiber. Ethanol and chloroform are employed as temperature-sensitive materials, which are placed on the outside of the fiber to detect temperature changes. When the phase-matching condition is met, the core mode couples with the surface plasma mode. The finite element method is used to perform all numerical simulations of sensor characteristics in the COMSOL software. The results show that the highest sensitivity of the sensor can reach 6.36 nm/°C and the maximum figure of merit (FOM) is 0.3440/°C in the range of −5 ~ 60 °C. To our knowledge, the achieved sensing characteristics are significantly better than those of the current PCF temperature sensors. Furthermore, excellent linearity with a polynomial fit R2 as high as 0.9981. The proposed sensor has exceptional performance in terms of temperature detection range, sensitivity, FOM, and fabrication, making it suitable for a wide variety of biochemical and medical applications.

Plasmonic photonic crystal fiber sensor for optical partial discharge detection

Detection of partial discharge (PD) is vital to reassure the operation reliability of high voltage (HV) electrical power systems. Optical detection methods have been developed in recent years due to their high sensitivity and immunity to electromagnetic interference. In this work, D-shaped photonic crystal fiber sensor based on surface plasmon resonance is reported for optical PD detection in HV equipment. A photochromic spirooxazine dye-doped silica sol–gel is utilized for sensing the UV radiation emitted from the PD. The sol–gel refractive index depends on the radiation intensity which affects the resonance wavelength where coupling occurs between the core and surface plasmon modes. The sensing performance is demonstrated with the help of full vectorial finite element method (FVFEM). The geometrical parameters are studied to maximize the sensor sensitivity where high sensitivity of 2.4 nm/mW.cm−2 is achieved. To the best of our knowledge, it is the first time to use a simple design of plasmonic PCF for optical PD detection.

A Reconfigurable Surface-Plasmon-Based Filter/Sensor Using D-Shaped Photonic Crystal Fiber.

A reconfigurable surface-plasmon-based filter/sensor using D-shaped photonic crystal fiber is proposed. Initially a D-shaped PCF is designed and optimized to realize the highly birefringence and by ensuring the single polarization filter. A tiny layer of silver is placed on the flat surface of the D-shaped fiber with a small half-circular opening to activate the plasmon modes. By the surface plasmon effect a maximum confinement loss of about 713 dB/cm is realized at the operating wavelength of 1.98 µm in X-polarized mode. At this wavelength the proposed fiber only allows Y-polarization and filters the X-polarization using surface plasmon resonance. It is also exhibiting maximum confinement loss of about 426 dB/cm at wavelength 1.92 µm wavelength for Y-polarization. At this 1.92 µm wavelength the proposed structure attenuated the Y-polarization completely and allowed X-polarization alone. The proposed PCF polarization filter can be extended as a sensor by adding an analyte outside this filter structure. The proposed sensor can detect even a small refractive index (RI) variation of analytes ranging from 1.34–1.37. This sensor provides the maximum sensitivity of about 5000 nm/RIU; it enables this sensor to be ideally suited for various biosensing and industrial applications.

Highly sensitive fiber optic biosensors with graphene-MoS2 heterostructure for hemoglobin detection

Two-dimensional materials, which can be used to modify sensor surfaces to increase sensor sensitivity, have important research in the field of sensors. In this paper, we design a highly sensitive D-shaped photonic crystal fiber sensor with graphene-MoS2 heterostructure for hemoglobin detection. The research utilized the finite element method and involved addition of different layers of graphene and MoS2 to the optical fiber sensing area, and it was determined that the hybrid nano-heterostructures made of monolayer graphene and bilayer MoS2 provided the greatest improvement in sensor performance. The sensor shows excellent detection performance in 1.33∼1.38 refractive index units. Using incident light in the wavelength ranges of 650 nm and 850 nm, the proposed sensor has a maximum wavelength sensitivity of 4700 nm/RIU, a maximum amplitude sensitivity of 327.5 RIU-1, and a resolution of 2.17×10−5 RIU. The range of hemoglobin concentrations detected with this sensor was 0 g/L∼241 g/L, with an average sensitivity of 0.7 nm/(g/L). A fiber biosensor was enhanced with graphene-MoS2 hybrid nanostructures, which exhibit excellent photoelectric properties and detection performance, enabling highly sensitive, highly accurate, and real-time hemoglobin detection. The result shows the significant research value and application prospects in the field of biomedical detection.

Wide refractive index detection range surface plasmon resonance sensor based on D-shaped photonic crystal fiber

We propose and simulate a surface plasmon resonance (SPR) refractive index (RI) sensor based on a novel D-shaped photonic crystal fiber. We used an open air hole coated with gold film to improve SPR effect. The sensor uses photonic crystal fiber with the same air holes diameter. The effects of structural parameters on resonance spectrum were analyzed by finite element method (FEM). Three SPR peaks were obtained in the wavelength range of 800–1300 nm. The maximum sensitivity is 5626.86 nm/RIU and the maximum resolution is 1.78 × 10−5 RIU at the refractive index of 1.38. The simulation results show that the refractive index detection range of the sensor is 1.26–1.38. Compared with other D-shaped structures, our sensor can measure larger RI ranges of the analyte.