Background

Terahertz (THz) electromagnetic systems and technology are rapidly growing in the marketplace in the fields of general analysis, diagnostics and communications. THz applications include, breathalyzers (local and remote), metabolic monitoring, CO monitoring in neonates, NO monitoring for asthma, ¹³CO_² for H. pylori infection, branched hydrocarbons for heart transplant rejection, NH₃ for kidney/liver dysfunction, acetone for diabetes, pollutant monitoring, trace gas detection and so much more. There are currently two main THz spectrometers, enabled by photoconductive antennae (PCA) on the market today, The older PCS LT‑GaAs and the newer PCA InGaAs. These two technologies offer cost advantages and operate at 1550 nm. This is key to developing a low‑cost and portable system. However, THz systems operating at 1550 nm are not very efficient and have a reduced bandwidth than those operating at 800 nm.

There need to be efficient and higher‑power photoconductive switches that operate at wavelengths near 1550 nm.

Technology Overview

UVic researchers have developed a Terahertz (THz) photoconductive antenna (PCA), a plasmon-enhanced, low temperature GaAs (PELT-GaAs) chip technology, that demonstrates improved performance at a lower anticipated cost when compared to InGaAs PCAs currently in the marketplace. Use of the PE-LT-GaAs chip leverages low-cost high-performance 1550 nm technology developed for fiber optics communications (instead of the expensive, competing 800 nm technology) without the concomitant sacrifice of performance necessitated by the use of InGaAs.

Benefits

• Have orders of magnitude higher resistivity (reduced dark current and noise), compared to competitors
• Shorter carrier lifetimes
• Lower cost (less material required and it is commercially available at lower cost).

Applications

• Biomedical
• Engineering
• Environmental