Plasmonic Refractive Index and Temperature Sensor Based on Graphene and LiNbO3

Abstract

A high-efficiency dual-purpose plasmonic perfect absorber sensor based on LiNbO3 and graphene layers was investigated in this paper for the refractive index and thermal sensing. The sensor design was kept simple for easy fabrication, comprising a LiNbO3 substrate with a quartz layer, thin layer of graphene, four gold nanorods, and a nanocavity in each unit cell. The nanocavity is located in the middle of the cell to facilitate the penetration of EM energy to the subsurface layers. The proposed sensor design achieved an output response of 99.9% reflection, which was easy to detect without having any specialized conditions for operability. The performance of the device was numerically investigated for the biomedical refractive index range of 1.33 to 1.40, yielding a sensitivity value of 981 nm/RIU with a figure-of-merit of 61.31 RIU−1. By including an additional polydimethylsiloxane polymer functional layer on the top, the device was also tested as a thermal sensor, which yielded a sensitivity level of −0.23 nm/°C.

Recent Development in Metasurfaces: A Focus on Sensing Applications

“…Apart from transmission- and reflection-based sensors [ 60 , 103 , 104 , 105 ], recent years have seen a rise in interest in the investigation of MS-based perfect EM-wave absorption for RI sensing applications [ 106 , 107 ]. Magnetic resonance can cause a sizable magnetic dipole to intermingle with the magnetic field of incident EM waves in artificial MSs, leading to the creation of an effective permeability [ 57 ].…”

Design and optimization of Bloch surface wave sensor with high sensitivity and quality factor using LiNbO3

“…28 Furthermore, LiNbO 3 possesses stronger field confinement capabilities, 29 and this characteristic is further enhanced when using LiNbO 3 thin films. 30 While there have been studies utilizing LiNbO 3 to manufacture various optical devices such as sensors, 31 modulators, 32 ring resonators, 33 and amplifiers, 34 research on using LiNbO 3 to enhance the sensitivity and quality factor of BSW sensors is relatively limited.…”

“…While there have been studies utilizing LiNbO3 to manufacture various optical devices such as sensors, 31 modulators, 32 ring resonators, 33 and amplifiers, 34 research on using LiNbO 3 to enhance the sensitivity and quality factor of BSW sensors is relatively limited.…”

A Concise Review of the Progress in Photonic Sensing Devices

“…The basic principle of photonic sensors is to detect changes in the optical properties of a material or a system caused by the parameter being measured [5,6]. For example, a photonic sensor can detect variations in the refractive index (RI), absorption, or fluorescence of a substance under observation, which can be correlated with the concentration of a target molecule or the presence of a specific substance [7,8]. They have a wide assortment of applications in different fields, containing: (I) medical applications, such as monitoring blood glucose levels, measuring oxygen saturation in blood, and detecting cancer cells [9]; (II) environmental surveillance, where these sensors can be used to monitor environmental parameters such as air and water quality, temperature, and humidity; (III) aerospace and defense: such as aircraft control systems, missile guidance, and remote sensing; (IV) structural health surveillance: photonic sensors can be employed to monitor the structural health of buildings, bridges, and other infrastructure [10][11][12]; (V) industrial process control: such as monitoring the temperature and pressure in chemical reactors and detecting gas leaks; (VI) communication networks: photonic sensors are used in communication networks for monitoring the performance of optical fibers and detecting fiber breaks; (VII) energy sector: photonic sensors can be used for surveillance of the condition of wind turbine blades, detecting pipeline leaks [13], and monitoring the temperature and pressure of oil and gas wells [14][15][16].…”