Luminescence and energy migration in a one-dimensional system: EuMgB5O10

Energy migration in one-dimensional Li6Eu(BO3)3

“…The temperature dependence of the migration process stems from the inhomogeneous broadening of the 5DQe7F0 transition [4,7]. The linewidth of this transition is 3.5 cm-' in Li6Eu(B03)3 at 4.2 K, which exceeds the homogeneous linewidth (less than 1 cm-' at these temperatures [ 161).…”

“…This has the same temperature dependence if we make the obvious assumption that x, is temperature independent. It appears that for all the Li,Eu( BO,) 3 : Nd3" samples the parameter R3 increases with T3, indicating a twosite non-resonant two-phonon assisted process [ 171, This process is commonly encountered in rare-earth compounds [ 4,10,18]. An illustration is given in fig. 4 for a sample of composition LlgEu0.999Nd0.00, ( B03) 3.…”

“…1 are found. These peaks belong to Eu3+ ions on nonregular crystallographic sites, a commonly observed phenomenon in Eu3+ compounds [ 4,7]. At least two types of non-regular ions can be distinguished in Li,Eu(B03)3.…”

“…2. At 300 K concentration quenching occurs above x= 0.85, which indicates that above this concentration the excitation energy can migrate over the Eu'+ sublattice to quenching sites [ 4,7]. Fig.…”

“…Experimental work has mostly focused on molecular crystals and Mn2+ compounds. In our laboratory attention has been directed to LnMgB5010 -an inorganic solid with a one-dimensional rare-earth sublattice -and the energy migration processes in the Gd3+ [ 31, Eu3+ [4] and Tb3+ [5] compounds were studied. It appeared that the energy migration was one-dimensional in EuMgBSO , o, quasi-one-dimensional in TbMgB5010 and three-dimensional in GdMgBSOlO.…”