A review of terahertz detectors

Abstract

Physics is the interplay of energy and matter. Energy, in the form of light, interacting with matter, principally in the solid state, underpins this topical review. The subject is developed carefully and methodically, beginning with basic definitions pertaining to terahertz detectors and terahertz radiation, then proceeding systematically to delineate characteristics of terahertz photons and terahertz detectors in more detail. In-between, the intimate connection linking terahertz sensors and terahertz sources is highlighted-an important aspect unfortunately often overlooked or ignored when terahertz detectors are discussed in isolation. At the centre of this topical review are the various physical mechanisms by which electromagnetic radiation of terahertz frequencies interacts with matter. The logic is to present first the underlying physical principles of detection before presenting the practical implementation in a specific device, rather than the other way around. A taxonomy of terahertz detectors is then proposed based on the underlying physical principles of detection. Following on from this classification, stateof-the-art terahertz detectors are surveyed and appraised; this overview constitutes the longest section of the review. Key detector parameters which inform applications are then presented and tabulated. Finally, the present state-of-the-art is anchored within the wider scientific context of historical developments and future prospects.

Towards Intense THz Spectroscopy on Water: Characterization of Optical Rectification by GaP, OH1, and DSTMS at OPA Wavelengths

“…Broader THz spectra can be measured with thin crystals [89,105], via more exotic detection schemes employing organic crystals with large linear birefringence [106][107][108][109][110], or with air-biased coherent detection (ABCD) at a cost of reduced DR (~30 dbm) [111][112][113]. While the detection techniques described above allow measuring both the amplitude as well as the phase of a THz field, power or intensity detectors are also available over the entire THz range [114,115].…”

Nondestructive Testing of Hollowing Deterioration of the Yungang Grottoes Based on THz-TDS

“…Compared with the conventional methods in the present nondestructive testing (NDT) field, such as magnetic particle testing, penetration testing, eddy current testing, radiographic testing, and ultrasonic testing, the typical wavelength of terahertz (THz) waves (300 µm) is larger than the size of small-scale structures; therefore, THz scattering in most objects occurs far less than for visible and near-infrared light, and the THz wave photon energy is commonly lower than the chemical bond energy, which means that THz waves can better penetrate most nonpolar materials. Furthermore, a THz wave is particularly suitable for NDT, and it allows the development of non-destructive, non-contact, non-ionizing methods that could advantageously replace other evaluation methods based on X-rays, ultrasound, and thermography [15][16][17][18][19][20][21].…”

Giant Photonic Response of Mexican-Hat Topological Semiconductors for Mid-infrared to Terahertz Applications

“…Other mechanisms for MIR/FIR/THz generation are also under active research [4][5][6][7][8][9][10] . On the photon detection side 11,12 , a variety of physical mechanisms can be utilized, including the thermal effect of MIR/FIR/THz radiations in e.g. a Golay cell, or the interaction between MIR/FIR/THz photons and electrons in e.g.…”