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arXiv · 1403.1652

Variable-delay Polarization Modulators for Cryogenic Millimeter-wave Applications

David T. Chuss·Joseph R. Eimer·Dale J. Fixsen·James Hinderks·Alan J. Kogut·Justin Lazear·Paul Mirel·Eric Switzer·George M. Voellmer·Edward J. Wollack
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Abstract

We describe the design, construction, and initial validation of the variable-delay polarization modulator (VPM) designed for the PIPER cosmic microwave background polarimeter. The VPM modulates between linear and circular polarization by introducing a variable phase delay between orthogonal linear polarizations. Each VPM has a diameter of 39 cm and is engineered to operate in a cryogenic environment (1.5 K). We describe the mechanical design and performance of the kinematic double-blade flexure and drive mechanism along with the construction of the high precision wire grid polarizers.

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David T. Chuss, Joseph R. Eimer, Dale J. Fixsen, James Hinderks, Alan J. Kogut, Justin Lazear, Paul Mirel, Eric Switzer, George M. Voellmer, Edward J. Wollack. 2014-05-28. Variable-delay Polarization Modulators for Cryogenic Millimeter-wave Applications. https://doi.org/10.1063/1.4879499

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