Polarization study and crystal-field analysis of the laser-selective excitation spectra ofHo3+ions inCaF

The luminescence properties of rare-earth ions in natural fluorite

“…The emission lines measured for the fluorite from Paszowice are different from those measured for synthetic crystals by Rector et al (1966), Dieke (1968), Tallant and Wright (1975), Seelbinder and Wright (1979) or Mujaji et al (1992). After Seelbinder and Wright (1979) or Mujaji et al (1992), the most intensive emission lines of the Ho 3? ion in the C 4v symmetry site were measured at 18,606, 18,490 and 18,448 cm -1 and identified as E 1 -Z 1 , E 1 -Z 4 and E 1 -Z 6 transitions, respectively, while for the C 3v symmetry site, the most intensive emission lines and transitions were 18,566 cm…”

“…Furthermore, some lines are present on the emission spectrum for holmium ion (Fig. 10a) at the shorter wavelength, whose energy should correspond to the transitions from the higher energy sublevels of 5 F 4 , 5 S 2 excited level (E 11-9 ) to the ground 5 I 8 level (Z 1-4 ), according to Mujaji et al (1992). Because the population of (E 11-9 ) states at T = 10 K is very small, this assumption should be 378, 399, 442, 451, 466, 473, 480, 363, 377 399, 440, 449, 461, 467, 473, 486 and Er 3?…”

“…and Ho 3? ions were determined, and luminescence lines were assigned to the C 4v and C 3v symmetry sites on the basis of EPR and electronic optical measurements (Rector et al 1966;Tallant and Wright 1975;Seelbinder and Wright 1979;Mujaji et al 1992). In the case of heavy-doped CaF 2 synthetic crystals and their analogues, other luminescence centers, such as pairs or clusters, have been discussed by researchers, too (Fenn et al 1973;Seelbinder and Wright 1979).…”

Site‐selective luminescence spectroscopy of Ho 3+ ions in CaF 2 and CsCdBr 3 crystals

“…The transitions arising from the two types of centres had comparable intensities. Symmetry assignment of the centres was achieved by polarisation measurements on suitably oriented crystals [7].…”

Hyperfine splittings and Zeeman infrared absorption ofTb3+-dopedCaF2andWells1, Jones2 2009Phys. Rev. B

“…The major center in CaF 2 :RE 3+ crystals is a C 4v symmetry RE 3+ -F − pair, with a charge compensating F − ion occupying an interstitial nearest-neighbor position along the ͗100͘ direction from the RE 3+ ion. [3][4][5][6][7][8][9][10][11][12][13][14] The CaF 2 and SrF 2 hosts differ in that, for RE 3+ ions beyond Ho 3+ in SrF 2 , the principal center has C 3v symmetry with a charge compensating interstitial fluorine ion located in the next-nearest-neighbor position along the ͗111͘ direction. By contrast, the major center in BaF 2 has trigonal C 3v symmetry throughout the RE 3+ series.…”