Oxyfluoride glass-ceramics: a bright future for laser cooling

The role of fluorine in high quantum yield oxyfluoride glasses and glass-ceramics

“…Consequently, improved fluorescence properties (emission intensity, lifetime, quantum efficiency) are obtained compared to the parent glass or their oxide counterparts [11]- [18]. In this sense, OGCs have been identified as interesting candidates for optical refrigeration purposes [19], [20]. Yttrium fluoride phase glass-ceramics are of particular interest since their performances for laser cooling applications have already been demonstrated as single crystals [5], [8], [21], [22].…”

Accurate Characterization of the Properties of the Rare-Earth-Doped Crystal for Laser Cooling

“…Since then, researchers have focused on exploring new promising potential materials for cryogenic optical cooling. So far, net cooling by laser has been demonstrated not only in a variety of rare-earth-doped (Yb 3+ -, Tm 3+ -, Er 3+ -and Ho 3+ -) bulk and nano crystals [2,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31], but also in glassy materials [32][33][34] and semiconductors of nano structure [35][36][37]. Among all the crystals tested, fluoride crystals have exhibited the best cooling performances [38][39][40].…”

Demonstration of laser cooling in a novel all oxide GAYY silica glass

“…To counter these limitations, our previous work concentrated on artificially creating a low phonon environment for the rare earth in high phonon energy oxide glasses, by the use of fluoride nanocrystals [20][21][22][23][24][25][26][27][28] . While this technique showed enhanced quantum efficiency of emission and increased lifetimes, the fabrication route was limited by the purity of starting materials and the process by which the glasses were made 29 , requiring a radical change in the glass making process.…”