High sensitivity multitasking non-reciprocity sensor using the photonic spin Hall effect

Abstract

A non-reciprocity sensor based on a layered structure with multitasking is proposed, which realizes biological detection and angle sensing. Through an asymmetrical arrangement of different dielectrics, the sensor obtains non-reciprocity on the forward and backward scales, thus achieving multi-scale sensing in different measurement ranges. The structure sets the analysis layer. Injecting the analyte into the analysis layers by locating the peak value of the photonic spin Hall effect (PSHE) displacement, cancer cells can accurately be distinguished from normal cells via refractive index (RI) detection on the forward scale. The measurement range is 1.569∼1.662, and the sensitivity (S) is 2.97 × 10−2 m/RIU. On the backward scale, the sensor is able to detect glucose solution with 0∼400 g/L concentrations (RI = 1.3323∼1.38), with S = 1.16 × 10−3 m/RIU. When the analysis layers are filled with air, high-precision angle sensing can be achieved in the terahertz range by locating the incident angle of the PSHE displacement peak; 30°∼45°, and 50°∼65° are the detection ranges, and the highest S can reach 0.032 THz/°. This sensor contributes to detecting cancer cells and biomedical blood glucose and offers a new way to the angle sensing.

Unveiling sub-bandgap energy-level structures on machined optical surfaces based on weak photo-luminescence

“…13,60 C stands the Dawson integral. Eqn (11) shows the rate equation of the free electrons at the conduction band on the ideal optical surface (without SDELs). The ideal surface represents the theoretical fused silica surfaces without point defects and surface defects.…”

“…8,9 Previous investigators have devoted themselves to the study of the methods and materials for optical transmission performance characterization and made big progress. 10,11 Notably, to achieve the desired optical performance, optical elements need to be shaped by precision machining. 12,13 Nonetheless, due to the fragile properties of optical materials, the mechanical processing of these optical elements is much complicated, 14,15 inevitably inducing plenty of micro-surface defects, like pits, 16 cracks, 17 and scratches, 17,18 which would severely decrease the LIDTs of the optical elements.…”

Graphene-based multifunctional humidity sensors with an ultrahigh current response

“…5,10,13 Many new and interesting approaches are proposed for multifunctional sensors. Among them are a wearable, breathable and stretchable electrocardiographic graphene-based sensor, 14 a multitasking non-reciprocity sensor using the photonic spin Hall effect, 15 a terahertz Janus sensor (active graphene layer), again, based on the photonic spin Hall effect, 16 an optical biochemical sensor (a metal active layer) based on the optical Tamm state for methane gas and glucose solution concentration detection, 17 and a wearable graphene-based smart face mask for real-time human respiration monitoring. 18 These examples are promising for expanding the capabilities and range of sensor applications.…”

Significant Enhancement of NO2 Detection Response in MoTe2 Nanostructures with a 1T′-2H Structure Mixture

“…Nanomaterials have promising potential for high-sensitivity detection due to their large surface-to-volume ratio, and various nanomaterials have been demonstrated to display a high sensitivity to a large variety of gas molecules, chemicals within the sensor, and biomedical field. – Recently, semiconducting two-dimensional transition-metal dichalcogenides (2D TMDs) have been considered promising gas-sensing materials due to their high surface-to-volume ratio as well as favorable surface energy levels for gas adsorption. – It has been demonstrated that 2D TMDs have high sensitivity to NO 2 gas at the subppb level …”