Full loss compensation in hybrid plasmonic waveguides under electrical pumping

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Surface plasmon polaritons (SPPs) enable sub-diffraction limit optics but suffer from high ohmic losses in metals.
• Practical applications of SPPs are limited by propagation losses, hindering nanoscale optical component design.

Purpose of the Study:

• To propose and demonstrate a novel method for efficient SPP amplification.
• To achieve lossless SPP guiding via electrical pumping in a deep-subwavelength structure.

Main Methods:

• Numerical demonstration of SPP amplification in a metal-insulator-semiconductor (MIS) waveguiding geometry.
• Utilizing a thin insulator layer to facilitate carrier injection and minimize leakage current.

Main Results:

• Full compensation for SPP propagation losses in the infrared spectrum.
• Achieved amplification at an exceptionally low pump current density of 0.8 kA/cm², an order of magnitude lower than previous studies.
• Minimized leakage current due to the thin insulator layer blocking majority carriers.

Conclusions:

• The proposed MIS structure enables efficient SPP amplification and lossless guiding.
• Low-density electrical pumping significantly reduces losses, paving the way for advanced nanophotonic and optoelectronic circuits.
• This work offers insights into overcoming fundamental limitations in SPP propagation for future integrated photonic devices.