Peysokhan, M.M.PeysokhanRostami, S.S.RostamiMobini, E.E.MobiniAlbrecht, A.R.A.R.AlbrechtKuhn, S.S.KuhnHein, S.S.HeinHupel, C.C.HupelNold, J.J.NoldHaarlammert, N.N.HaarlammertSchreiber, T.T.SchreiberEberhardt, R.R.EberhardtFlores, A.A.FloresTünnermann, A.A.TünnermannSheik-Bahae, M.M.Sheik-BahaeMafi, A.A.Mafi2022-03-062022-03-062021https://publica.fraunhofer.de/handle/publica/26783710.1021/acsomega.1c00116Laser cooling of a solid is achieved when a coherent laser illuminates the material, and the heat is extracted by annihilation of phonons resulting in anti-Stokes fluorescence. Over the past year, net solid-state laser cooling was successfully demonstrated for the first time in Yb-doped silica glass in both bulk samples and fibers. Here, we report more than 6 K of cooling below the ambient temperature, which is the lowest temperature achieved in solid-state laser cooling of silica glass to date to the best of our knowledge. We present details on the experiment performed using a 20 W laser operating at a 1035 nm wavelength and temperature measurements using both a thermal camera and the differential luminescence thermometry technique.en620journal article