Modal Analysis of Plasmon-Polaritons in Plasmonic THz Detector Integrated with Two-Dimensional Nano-Antennas

Plasmon-polariton modes in an InGaAs-HEMT-based plasmonic THz detector integrated with 2D nano-antennas are theoretically investigated. We show that the incident THz wave polarized in the channel width direction can be converted into a cross-polarized plasmon mode in the channel length direction via the 2D nano-antennas, indicating a possibility of realizing polarization-insensitive THz detection by the plasmonic detector.