1. On the Efficiency of Infrared Filters in Optical Cryostats
- Author
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Laurent Guyon, Mathieu Melich, Roman E. Boltnev, Pierre-Etienne Wolf, Fabien Bonnet, Hélium : du fondamental aux applications (HELFA), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Institute of Energy Problems of Chemical Physics, Russian Academy of Sciences [Moscow] (RAS), and ANR-06-BLAN-0098,HEVEPOR,Un système modèle pour les transitions de phase en milieu désordonné : l'adsorption de l'hélium dans les aérogels(2006)
- Subjects
Cryostat ,Materials science ,Infrared ,chemistry.chemical_element ,02 engineering and technology ,Optical cryostat ,01 natural sciences ,Upper and lower bounds ,Optics ,PACS numbers: 07.20.Mc, 44.40.+a, 07.57.-c ,Thermal radiation ,0103 physical sciences ,General Materials Science ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,[PHYS.COND.CM-DS-NN]Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn] ,010306 general physics ,Helium ,Infrared cut-off filter ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,business.industry ,Condensation ,Aerogels ,Aerogel ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Low temperature shutters ,chemistry ,Optoelectronics ,Infrared filters ,0210 nano-technology ,business - Abstract
8 pages; International audience; In an optical cryostat, the sample temperature is limited by the 300 K ther- mal radiation transmitted through the observation windows. As discussed in this pa- per, the corresponding heat load should be brought much below the μW level by using suitable cold IR filters. However, there are situations where one wants to di- rectly check the absence of IR heating by running the same experiment with the cold observation windows either open or totally blocked. We describe a particular example which is the study of helium condensation in a silica aerogel. On this aim, we devel- oped a simple and compact magnetic system able to move metallic shutters inside our optical cryostat. This allows us to set an upper bound of 1 μW for the effect of 300 K thermal radiation on our sample. We discuss the relevance of this result to the operation of optical dilution refrigerators.
- Published
- 2011
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