Investigation of 4f(7) levels of Eu2+ ions in KMgF3 crystal by two-photon excitation spectroscopy

Intraconfigurational 4f(7)-4f(7) transitions of Eu2+ in KMgF3 are investiga ted by two-photon excitation (TPE) spectroscopy. The emissions due to the P -6(7/2) --> S-8(7/2) and I-6(7/2) --> S-8(7/2) transitions are obtained by the two-photon excitation into the D-6(9/2) at 10 K. It is found that the T PE spectrum of the I-6(7/2) --> S-8(7/2) emission is different from that of the P-6(7/2) --> S-8(7/2) emission. The result is discussed in terms of th e relative position between the lowest crystal-field component of the I-6(7 /2) level and the lowest 4f(6)5d level of Eu2+ at the cubic and non-cubic s ites in KMgF3. (C) 2000 Elsevier Science B.V. All rights reserved.