Modelling thermal parasitic load lines for an optical refrigerator

Cryogenic Engineering Conference 2015

材料科学;物理学

Martin, K.W.^1,3 ; Shomacker, J.^2 ; Fraser, T.^3 ; Dodson, C.^3

Applied Technology Associ., 1300 Britt St. SE, Albuquerque

NM

87123-3353, United States^1

Rensselaer Polytechnic Institute, 110 8th St., Troy

NY

12180, United States^2

Spacecraft Component Thermal Research Group at Air Force Research Labs Kirtland, AFB, NM

87117-5776, United States^3

关键词: Anti-Stokes fluorescence;    Cryogenic temperatures;    Fluorescence reabsorption;    Fluorescence thermometry;    Optical refrigeration;    Solid-state cooling;    System level optimization;    Temperature dependent;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/101/1/012051/pdf
DOI  :  10.1088/1757-899X/101/1/012051

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Optical refrigeration is currently the only completely solid state cooling method capable of reaching cryogenic temperatures from room temperature. Optical cooling utilizing Yb:YLF as the refrigerant crystal has resulted in temperatures lower than 123K measured via a fluorescence thermometry technique. However, to be useful as a refrigerator this cooling crystal must be attached to a sensor or other payload. The phenomenology behind laser cooling, known as anti-Stokes fluorescence, has a relatively low efficiency which makes the system level optimization and limitation of parasitic losses imperative. We propose and model a variety of potential designs for a final optical refrigerator, enclosure and thermal link; calculate conductive and radiative losses, and estimate direct fluorescence reabsorption. We generate parasitic load-lines; these curves define temperature-dependent minimum heat lift thresholds that must be achieved to generate cooling for detectors.