Accession Number : ADA599630


Title :   Cryogenic Optical Refrigeration


Descriptive Note : Journal article


Corporate Author : AIR FORCE RESEARCH LAB KIRTLAND AFB NM SPACE VEHICLES DIRECTORATE


Personal Author(s) : Seletskiy, Denis V ; Hehlen, Markus P ; Epstein, Richard I ; Sheik-Bahae, Mansoor


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a599630.pdf


Report Date : 22 Mar 2012


Pagination or Media Count : 31


Abstract : We review the field of laser cooling of solids, focusing our attention on the recent advances in cryogenic cooling of an ytterbium-doped fluoride crystal (Yb[expn 3+]:YLiF4). Recently, bulk cooling in this material to 155 K has been observed upon excitation near the lowest-energy (E4 E5) crystal-field resonance of Yb(expn 3+). Furthermore, local cooling in the same material to a minimum achievable temperature of 110 K has been measured, in agreement with the predictions of the laser cooling model. This value is limited only by the current material purity. Advanced material synthesis approaches reviewed here would allow reaching temperatures approaching 80 K. Current results and projected improvements position optical refrigeration as the only viable all-solid-state cooling approach for cryogenic temperatures.


Descriptors :   *CRYOGENICS , *REFRIGERATION SYSTEMS , *SOLID STATE LASERS , COOLING , DOPING , EFFICIENCY , FLUORIDES , LASERS , LOW TEMPERATURE , OPTICS , SYNTHESIS(CHEMISTRY) , TEMPERATURE , YTTERBIUM


Subject Categories : Lasers and Masers
      Air Condition, Heating, Lighting & Ventilating
      Optics
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE