Dual-function photonic spin Hall effect sensor for high-precision refractive index sensing and graphene layer...

Area of Science:

• Optoelectronics
• Nanotechnology
• Sensor Technology

Background:

• The photonic spin Hall effect (PSHE) is a phenomenon involving the separation of light polarizations.
• Graphene's unique properties make it suitable for advanced sensing applications.
• Accurate detection of refractive index and material layers is crucial in various scientific fields.

Purpose of the Study:

• To propose and analyze a novel photonic spin Hall effect (PSHE) sensor.
• To demonstrate the sensor's capability for high-precision refractive index (RI) detection.
• To validate the sensor's application in determining the number of graphene layers.

Main Methods:

• Numerical analysis using the transfer matrix method.
• Introduction of graphene into a layered topology to induce PSHE.
• Investigation of H and V polarization displacements for sensing applications.

Main Results:

• The H polarization shift demonstrated a measurement range (MR) of 1.1-1.5 RIU, sensitivity (S) of 127.85 degrees/RIU, figure of merit (FOM) of 2412, and detection limit (DL) of 2.08×10^-5.
• The V polarization shift showed a MR of 1-9 layers and S of 4.54 degrees/layer for graphene detection.
• The sensor's performance was analyzed considering parameters like chemical potential, relaxation time, temperature, and dielectric loss.

Conclusions:

• The proposed PSHE sensor exhibits superior performance for RI detection, applicable to solids, liquids, and gases.
• The sensor effectively detects the number of graphene layers, offering a new avenue for graphene characterization.
• This work provides a theoretical foundation for designing novel multifunctional sensors based on PSHE.