- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Ultrasensitive Microfiber Refractive Index Sensor Based on Mach-Zehnder Interference of Core Offset Structure
摘要： An ultrasensitive microfiber refractive index (RI) sensor was proposed and demonstrated based on the core offset Mach-Zehnder interference (MZI) fiber structure. It consisted of a core offset single-mode fiber (SMF) fusion spliced between two SMFs, where the center SMF was tapered to diameter of few micrometers. The experimental results showed that the sensor exhibits an ultrahigh RI sensitivity of 16485 nm /RIU (RI unit) within the RI range between 1.410 and 1.413 where the core offset and fiber diameter were 7.5 μm and 9 μm, tapered respectively. This proposed fiber sensor has the great potential as a base for biosensor in applications of air pollution monitoring, chemical elements detection and medical diagnostics.
关键词： core offset,refractive index sensing,microfiber
更新于2025-09-16 10:30:52
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Loss-Induced Resonant Refractive Index Sensing using Total Internal Reflection Phase Shift
摘要： Refractometry has a variety of applications in chemistry, biotechnology, or food industry. A number of sensor systems are available to analyze the refractive index of liquid solutions or even biological tissue. We present a novel technique that aims at recording local distributions of refractive indices. The approach relies on the phase shift upon total internal reflection (TIR) and uses an extremely short Fabry-Pérot microcavity of less than 3 μm effective length as the key element to precisely measure refractive indices at less than 100 μm spatial resolution.
关键词： Fabry-Pérot microcavity,Total Internal Reflection,Refractometry,Refractive Index Sensing
更新于2025-09-12 10:27:22
-
Novel polymer waveguide-based surface plasmon resonance (SPR) sensor
摘要： A novel polymer waveguide for surface plasmon resonance (SPR) sensing is theoretically proposed and experimentally demonstrated. The waveguide sensor simply consists of a polymer and a thin gold film on a silica layer. According to the multilayer transfer-matrix theory and the multiple reflection theory, a formula describing the reflectivity of total light power is deduced and analyzed, which is related to the dielectric constant of both the waveguide and the metal, the thickness of the metal film, and the length of the sensing area. By the addition of liquids with refractive indices ranging from 1.40 to 1.47 in the sensing area, the proposed polymer waveguide-based surface plasmon resonance sensor exhibited an experimental sensitivity of 1489 dB/RIU. With a refractive index range between 1.45 and 1.47 beyond the measurement range of typical SPR fiber based sensors, the reported device operates with very high sensitivity. The proposed portable, compact, and simple polymer waveguide-based surface plasmon resonance sensor shows potential for low cost and on-chip multiple channel sensing for practical applications.
关键词： refractive index sensing,polymer waveguide,surface plasmon resonance (SPR),optical power detection
更新于2025-09-12 10:27:22
-
Quasi-D-Shaped Fiber Optic Plasmonic Biosensor for High-Index Analyte Detection
摘要： In this paper, we propose a highly sensitive quasi-D-shaped fiber optic biosensor for detection of high refractive index (RI) liquid analytes via surface plasmon resonance. The main mechanism of sensing is interplay between photonic crystal fiber fundamental mode and plasmonic mode which leads to formation of different resonance peaks depending on the analyte RI. We numerically analyze the structure sensitivity to design parameters and demonstrate the sensing performance of the proposed biosensor using both spectral sensitivity and amplitude sensitivity methods. The proposed biosensor has a RI detection range of 0.15 refractive index unit (RIU) from 1.45 to 1.6. The sensor exhibits linear sensing performance with a RI spectral sensitivity of 9300 nm/RIU for analyte RI ranging from 1.45 to 1.525, 1176 nm/RIU for analyte RI ranging from 1.525 to 1.6 and in particular, 11800 nm/RIU for analyte RI between 1.475 and 1.5. Furthermore, an average RI sensitivity of 4800 nm/RIU for analyte RI ranging from 1.45 to 1.6 is demonstrated. We also study the amplitude sensitivities of the proposed sensor which show promising maximum values of 183.6 RIU-1 for 785 nm excitation and 820 RIU-1 for 1050 nm excitation. Due to the simple structure of the proposed biosensor, large detection range, high sensitivity and promising linear sensing performance, the proposed biosensor can be a promising candidate for detecting various high RI chemical and biochemical samples.
关键词： plasmonic biosensor,photonic crystal fiber,high index analyte detection,Fiber optic sensor,refractive index sensing
更新于2025-09-11 14:15:04
-
Plasmon induced transparency like transmission properties in compact MIM waveguide side-coupled with U-cavity
摘要： Surface plasmon polaritons (SPPs) can overcome the limitation of diffraction and control light at nanoscale, thus becoming a hotspot in recent years. SPPs based metal-insulator-metal (MIM) plasmonic waveguides using U-cavity and slot cavity are designed. The transmission characteristics are numerically simulated and verified by the coupled mode theory (CMT). Meanwhile, the effects of changing the geometric parameters on the transmission characteristics are also studied. Single and double plasmon induced transparency (PIT) effects are realized through the coupling and the destructive interfering between the transmission paths. Furthermore, characteristics of the refractive index sensing as well as the slow light and fast light effects are also investigated. We hope the designed waveguide structures along with their transmission characteristics have potential application prospects in the area of nanoscale integrated optical devices, such as filters, sensors, switches, slow/fast light devices, and other optoelectronic circuits.
关键词： refractive index sensing,slow light,U-cavity,Surface plasmon polaritons,slot cavity,plasmon induced transparency,MIM plasmonic waveguides,fast light
更新于2025-09-11 14:15:04
-
Rectangular and sinusoidal Au-Grating as plasmonic sensor: A comparative study
摘要： Sensitivity of surface plasmon resonance sensor (SPRS) is mainly associated to efficient excitation of surface plasmon polaritons (SPPs) waves. In this work, effect of 50 nm thick Au film designed as rectangular and sinusoidal grating structure on glass substrate has been explored by finite element analysis (FEA) using COMSOL Multiphysics 5.3a. The comparison between the rectangular and sinusoidal gratings for efficient sensing has been presented here. Slit width (SW) for grating device has been optimized by applying far-field and near-field analysis while periodicity of grating structure is kept constant. Far field transmission spectra for both devices have been analyzed by illuminating the grating device through excitation port from the substrate side. Resonance wavelength (RW) dips for plasmonic grating device has been examined in each transmission spectrum for different values of refractive indices (RI). The sensitivity of plasmonic grating device has been calculated by measuring the shift in resonance wavelength by varying refractive index of analyte. The sinusoidal grating supporting fundamental plasmonic mode is found to be more sensitive (717 nm/RIU) as compared to simple rectangular grating (693 nm/RIU). Being highly sensitive to minute change in refractive index, such devices are efficiently applicable in real life.
关键词： Plasmonic sensor,Sinusoidal grating,Finite element analysis,Refractive index sensing,Sensitivity,Rectangular grating
更新于2025-09-11 14:15:04
-
U-shaped photonic quasi-crystal fiber sensor with high sensitivity based on surface plasmon resonance
摘要： A U-shaped external photonic quasi-crystal fiber (PQF) sensor based on surface plasmon resonance is proposed for refractive index (RI) sensing. The advantages of sensing with metal/liquid surface plasmon polariton (SPP) mode are summarized. The gold/liquid SPP mode is excited and used for sensing in the U-shaped external PQF, which can detect a small variation of the analyte RI. The maximum sensitivity of the sensor is 33600 nm/RIU, and the average sensitivity is 21643.75 nm/RIU within the detection RI range of 1.420–1.436. The U-shaped PQF sensor will provide a new design idea for the RI sensor with high sensitivity.
关键词： U-shaped photonic quasi-crystal fiber,surface plasmon resonance,refractive index sensing,high sensitivity
更新于2025-09-11 14:15:04
-
Theoretical and Experimental Investigation of an All-Fiber Waveguide Coupled Surface Plasmon Resonance Sensor With Au–ZnO–Au Sandwich Structure
摘要： In this paper, we proposed an all-fiber waveguide coupled surface Plasmon resonance (SPR) sensor which was designed and fabricated with Au-ZnO-Au sandwich multi-layer structure. Based on the transfer matrix method (TMM), the theoretical modeling of the proposed sensor structure was investigated. The influence of the layer thickness on the transmission spectrum of the sensor was studied numerically, in order to optimize each layer thickness, leading to sensitivity enhancement in the infrared spectral range. Meanwhile, an experimental testbed for the refractive index measurement was implemented based on the proposed all-fiber waveguide coupled SPR sensor. Using this waveguide coupled SPR sensor, the refractive index sensing was realized with a sensitivity enhancement of 7%—131% compared with conventional SPR sensors.
关键词： refractive index sensing,optical fiber,Surface plasmon resonance,waveguide coupled,sensitivity
更新于2025-09-11 14:15:04
-
Highly Sensitive, Affordable, and Adaptable Refractive Index Sensing with Silicon‐Based Dielectric Metasurfaces
摘要： A sensing platform is presented that uses dielectric Huygens source metasurfaces to measure refractive index changes in a microfluidic channel with experimentally measured sensitivity of 323 nm RIU?1, a figure of merit (FOM) of 5.4, and a response of 8.2 (820%) change in transmittance per refractive index unit (T/RIU). Changes in the refractive index of liquids flown through the channel are measured by single-wavelength transmittance measurement, requiring only a simple light source and photodetector, significantly reducing device expense in comparison to state-of-the-art refractive index sensing technologies. A technoeconomic analysis predicts a device costing ≈$2400 that is capable of detecting refractive index changes of the order of 2*10?8. The metasurfaces utilized are low profile, scalable, and use materials and fabrication processes compatible with CMOS and other technologies making them suitable for device integration. The Huygens metasurface system, characterized by spectrally overlapping electric and magnetic dipole modes, offers a high degree of customizability. Interplay between the two resonances may be controlled via metasurface geometry, leading to tunability of device sensitivity and measurement range. Ultrahigh sensitivity of 350 nm RIU?1 with FOM of 219, corresponding to single-wavelength sensitivity of 360 RIU?1, is demonstrated computationally through use of antisymmetric resonances of a Huygens metasurface illuminated at small incidence angles.
关键词： metasurface,refractive index sensing,subwavelength structures,biosensing,nanophotonics
更新于2025-09-04 15:30:14