A simple interferometer for the characterization of sources at terahertz frequencies

Abstract

The design and performance of a simple and compact far-infrared Fourier-transform spectrometer for the characterization of sources is described. The spectrometer works as a Michelson interferometer without a beam splitter and employs a Golay cell or a pyroelectric detector. A pair of flat lamellar mirrors with a computer-controlled displacement introduces a precisely defined phase difference between two parallel beams of nearly equal radiated power. The interferometer is intended for operation at frequencies between 0.1 and 3 THz with a frequency resolution of 6 GHz, and is used to characterize both continuous-wave and pulsed sources.

Compact Superconducting Terahertz Source Operating in Liquid Nitrogen

“…The ratio between the power and the bolometer readout is 2.1 × 10 −3 W=V. For the fast Fourier transform, the frequency resolution of the Michelson interferometer is given by Δf ¼ c=ð2d max Þ cosðθÞ, where d max is the maximum differential displacement of the lamellar mirrors and θ the angle of incidence [50]. In our setup, d max ¼ 20 mm and θ ∼ 0°; therefore, Δf can be estimated as 7.5 GHz.…”

Engineering and characterization of a packaged high-Tcsuperconducting terahertz source module

“…The noise equivalent power of the detector was 1.4×10 −13 W/Hz 1/2 . To measure the emission frequency, we used a home-built Fourier transform infrared (FT-IR) spectrometer consisting of a pair of flat lamellar mirrors (not shown here) [36]. The frequency resolution of the spectrometer is given by ∆f ∼ c/2d max , where d max is the maximum differential displacement of the lamellar mirror and c is the speed of light.…”

Terahertz-wave emission from Bi2212 intrinsic Josephson junctions: a review on recent progress

“…5 (b) laboratory-built interferometers are also used for spectroscopy. A simple lamellar interferometer [93] was introduced by Wang et al, as shown in Fig. 5 (c) [94].…”