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Updated: Jul 4, 2025
A Simple Dewar/Cryostat for Thermally Equilibrating Samples at Known Temperatures for Accurate Cryogenic Luminescence Measurements
Published on: July 19, 2016
Development and validation of a cryogenic far-infrared diffraction grating spectrometer used to post-disperse the
Alicia M Anderson1,2,3, David A Naylor1, Brad G Gom1
1Department of Physics and Astronomy, University of Lethbridge, 4401 University Dr. W, Lethbridge, Alberta T1K 3M4, Canada.
Abstract:
Recent advances in far-infrared detector technology have led to increases in raw sensitivity of more than an order of magnitude over previous state-of-the-art detectors. With such sensitivity, photon noise becomes the dominant noise component, even when using cryogenically cooled optics, unless a method of restricting the spectral bandpass is employed. The leading instrument concept features reflecting diffraction gratings, which post-disperse the light that has been modulated by a polarizing Fourier transform spectrometer (FTS) onto a detector array, thereby reducing the photon noise on each detector. This paper discusses the development of a cryogenic (4 K) diffraction grating spectrometer that operates over the wavelength range of 285 to 500 μm and was used to post-disperse the output from a room-temperature polarizing FTS. Measurements of the grating spectral response and diffraction efficiency are presented as a function of both wavelength and polarization to characterize the instrumental performance.
