Interferometric Measurement of Far Infrared Plasmons via Resonant Homodyne Mixing

TL;DR

This paper introduces a tunable terahertz plasmonic interferometer with an integrated resonant homodyne detector, enabling direct DC measurement of plasma waves for potential on-chip spectrometry applications.

Contribution

It presents a novel electrically tunable plasmonic interferometer with integrated detection, advancing terahertz spectroscopy and on-chip spectrometer development.

Findings

Demonstrated tunable two-path plasmonic interferometers.

Achieved direct DC detection via resonant homodyne mixing.

Showed potential for chip-scale terahertz spectrometry.

Abstract

We present an electrically tunable terahertz two dimensional plasmonic interferometer with an integrated detection element that down converts the terahertz fields to a DC signal. The integrated detector utilizes a resonant plasmonic homodyne mixing mechanism that measures the component of the plasma waves in-phase with an excitation field functioning as the local oscillator. Plasmonic interferometers with two independently tuned paths are studied. These devices demonstrate a means for developing a spectrometer-on-a-chip where the tuning of electrical length plays a role analogous to that of physical path length in macroscopic Fourier transform interferometers.