Graphene-assisted electromagnetically induced transparency-like terahertz bio-sensor for ultrasensitive detection...

Area of Science:

• Terahertz (THz) metamaterials
• Biosensing technologies
• Graphene-based devices

Background:

• Terahertz metamaterials are increasingly researched for biosensing applications.
• Enhancing biosensor sensitivity using optical pumping remains an underexplored area.
• Graphene's unique properties offer potential for advanced metamaterial designs.

Purpose of the Study:

• To develop an optics-enhanced terahertz metamaterial biosensor utilizing graphene.
• To investigate the use of optical pumping to improve biosensing sensitivity.
• To detect glycine with high sensitivity using the proposed biosensing platform.

Main Methods:

• Fabrication of a graphene-based electromagnetically induced transparency-like (EIT-like) terahertz metamaterial biosensor.
• Detection of glycine via amplitude modulation and optical pumping.
• Analysis of transmission spectrum amplitude changes with varying optical energy density.

Main Results:

• Achieved a limit of detection (LOD) of 1 pg/mL for glycine.
• Demonstrated optics-enhanced sensing with a significant increase in transmission spectrum amplitude.
• Observed a quasi-linear relationship between transmission amplitude change and optical energy density.
• Reported a maximum amplitude rate of change (AR) of 857.5% for 32 pg/mL glycine at 119.7 µJ/cm².
• Successfully detected 1 pg/mL glycine, which was undetectable without optical enhancement.

Conclusions:

• The graphene-based terahertz metamaterial biosensor shows significantly enhanced sensitivity under optical pumping.
• Optical pumping offers a promising method for improving the detection precision of low analyte concentrations.
• This approach presents a new direction for the practical application of terahertz metamaterials in biosensing.