An on-chip near-field terahertz probe and detector

The advantageous properties of terahertz waves, such as their transmission through objects opaque to visible light, are attracting attention for imaging applications 1 , 2 . A promising approach for achieving high spatial resolution is the use of near-field imaging 3 , 4 . Although this method has been well established in the visible 5 , 6 and microwave 7 , 8 regions, it is challenging to perform in the terahertz region. In the terahertz techniques investigated to date 9 , 10 , 11 , detectors have been located remotely from the probe, which degrades sensitivity, and the influence of far-field waves is unavoidable. Here we present a new integrated detection device for terahertz near-field imaging in which all the necessary detection components—an aperture, a probe and a terahertz detector—are integrated on one semiconductor chip, which is cryogenically cooled. This scheme allows highly sensitive, high-resolution detection of the evanescent field alone and promises new capabilities for high-resolution terahertz imaging. Here researchers report an integrated detection device for terahertz near-field imaging in which all the necessary detection components, that is, an aperture, a probe and a terahertz detector, are integrated on one cryogenically cooled, semiconductor chip. This scheme enables highly sensitive, high-resolution detection of the evanescent field and promises new capabilities for high-resolution terahertz imaging.