Researchers have developed a novel quantum detector that dramatically improves the detection of terahertz (THz) radiation, achieving a sensitivity boost of nearly 20 times compared with earlier designs. The breakthrough combines quantum physics with a specially engineered metasurface, offering a compact and efficient solution for one of the most challenging regions of the electromagnetic spectrum.

Figure 1. Terahertz (thz) Radiation.

The device operates using the in-plane photoelectric effect, a quantum process in which terahertz photons transfer energy to electrons confined within a two-dimensional electron gas. Unlike conventional detectors, this mechanism does not require photons to exceed a minimum energy threshold, enabling efficient detection of low-energy radiation.

To enhance performance, the researchers integrated the detector into a metasurface featuring a repeating brickwork pattern. This structure captures incoming terahertz waves and concentrates them into microscopic gaps where multiple detector elements are positioned. By combining the signals from many detection sites, the device collects far more radiation than previous single-antenna designs, resulting in a much stronger electrical response. Figure 1 shows Terahertz (thz) Radiation.

Tests showed a responsivity of 2.7 amperes per watt and an external quantum efficiency of 2.1 percent at 1.9 THz, representing a significant improvement over earlier photoelectric tunable-step detector. The detector also operates without dark current, reducing electronic noise and improving measurement accuracy.

Because the metasurface itself focuses incoming radiation, the system eliminates the need for bulky external optics such as silicon lenses [1]. Its planar architecture is compatible with established semiconductor manufacturing techniques, making future integration with electronic circuits more practical.

The technology could benefit a wide range of applications, including next-generation wireless communications, medical imaging, astronomy, industrial inspection, and environmental monitoring. By combining advanced metasurface engineering with quantum detection principles, the new device marks an important step toward more sensitive, compact, and scalable terahertz technologies.

References:

1. https://scitechdaily.com/this-quantum-detector-boosts-terahertz-sensitivity-by-20-times/

Cite this article:

Keerthana S (2026), Quantum Technology Pushes Terahertz Sensing to New Heights, AnaTechMaz, pp.522