Localized surface plasmon resonance frequency tuning in highly doped InAsSb/GaSb one-dimensional nanostructures

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Localized Surface Plasmon Resonance (LSPR) is crucial for optical applications.
• Semiconductor nanostructures offer tunable plasmonic properties.
• Mid-infrared (MIR) sensing requires materials with specific LSPR characteristics.

Purpose of the Study:

• To analyze the impact of doping level and nanoribbon width on LSPR in Si-doped InAsSb/GaSb nanostructures.
• To demonstrate the tunability of LSPR for MIR applications (8-20 μm).
• To evaluate the potential of these nanostructures for biosensing.

Main Methods:

• Fabrication of 1D periodic gratings of Si-doped InAsSb/GaSb nanostructures using a large-area technique.
• Characterization of LSPR properties via reflectance measurements.
• Numerical simulations to confirm experimental observations.
• Surface plasmon resonance (SPR) sensing experiments with absorbing polymer layers.

Main Results:

• Increasing doping level blueshifted the LSPR peak; increasing ribbon width redshifted it.
• LSPR properties were fine-tuned within the 8-20 μm range.
• Achieved a quality factor of 16, sensitivity of 700 nm/RIU, and figure of merit of 2.5 for SPR sensing.
• Demonstrated Si-doped InAsSb/GaSb as a low-loss, high-sensitivity material.

Conclusions:

• Si-doped InAsSb/GaSb nanostructures provide tunable LSPR in the MIR region.
• The material exhibits excellent performance metrics for SPR sensing.
• These findings highlight the potential of Si-doped InAsSb/GaSb for developing advanced MIR biosensing devices.