title: Comparison of Thermal Detector Arrays for Off-Axis THz Holography and Real-Time THz Imaging.
abstract: In terahertz (THz) materials science, imaging by scanning prevails when low power THz sources are used. However, the application of array detectors operating with high power THz sources is increasingly reported. We compare the imaging properties of four different array detectors that are able to record THz radiation directly. Two micro-bolometer arrays are designed for infrared imaging in the 8-14 μm wavelength range, but are based on different absorber materials (i) vanadium oxide; (ii) amorphous silicon; (iii) a micro-bolometer array optimized for recording THz radiation based on silicon nitride; and (iv) a pyroelectric array detector for THz beam profile measurements. THz wavelengths of 96.5 μm, 118.8 μm, and 393.6 μm from a powerful far infrared laser were used to assess the technical performance in terms of signal to noise ratio, detector response and detectivity. The usefulness of the detectors for beam profiling and digital holography is assessed. Finally, the potential and limitation for real-time digital holography are discussed.
authors: Reliability Science and Technology Laboratory, Empa, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland. erwin.hack@empa.ch.
authors: Erwin
authors: E
authors: Hack
authors: Reliability Science and Technology Laboratory, Empa, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland. lorenzo.valzania@empa.ch.
authors: Lorenzo
authors: L
authors: Valzania
authors: Institute of Applied Physics, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland. gregory.gaeumann@iap.unibe.ch.
authors: Gregory
authors: G
authors: Gäumann
authors: SwissFEL Laser Group, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland. mostafa.shalaby@psi.ch.
authors: Mostafa
authors: M
authors: Shalaby
authors: SwissFEL Laser Group, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland. christoph.hauri@psi.ch.
authors: Christoph P
authors: CP
authors: Hauri
authors: Reliability Science and Technology Laboratory, Empa, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland. peter.zolliker@empa.ch.
authors: Peter
authors: P
authors: Zolliker
mesh_terms: D004867:Equipment Design; D006696:Holography; D007834:Lasers; D008027:Light; D059629:Signal-To-Noise Ratio; D012825:Silicon / Q000737:chemistry; D055053:Terahertz Radiation; D017968:Vanadium Compounds / Q000737:chemistry
chemical_list: D017968:Vanadium Compounds; D012825:Silicon
keywords: array detector; digital holography; micro-bolometer; pyroelectric detector; real time imaging; terahertz