Spectroscopy and Crystal-Field Analysis of Low -Symmetry Er${}^{3+}$ Centres in K${}_2$YF${}_5$ Microparticles

Pratik S. Solanki, Michael F. Reid, Jon-Paul R. Wells

K${}_2$YF${}_5$ crystals doped with lanthanide ions have a variety of possible optical applications. Owing to the low symmetry of the system, the crystal structure cannot be unambiguou…