NDA@SZTAKI

Effect of symmetry reduction on the electronic transitions in polytypic GdAl3(BO3)4:Eu:Tb crystals

Lengyel, K.

Beregi, E.

FĂśldvĂĄri, I.

Corradi, G.

KovĂĄcs, L.

Solarz, P.

Ryba-Romanowski, W.

Elsevier

2016

QC06 Physics of condensed matter / szilĂĄrdtestfizika

QD05 Crystallography / kristĂĄlytan

The existence of a recently described monoclinic phase (C2/c, Z=8) in addition to the well-known Huntite type rhombohedral (R32) polytypic modification of the GdAl3(BO3)4 (GAB) crystal at room temperature provides a unique possibility to investigate the incorporation of rare earth dopants into slightly modified crystal lattice by spectroscopic
methods. In these characteristic GAB structures the dopant ions, e.g Tb3+ or Eu3+ , possess slightly different neighbor geometries and local symmetries. The Tb3+:7F6 → 5D4 and Eu3+:7F0,1,2 → 5D0,1,2 electronic transitions were successfully identified in the absorption spectra
using polarization, concentration and temperature dependent measurements in both polytypic modifications. The positions of the investigated Tb lines are shifted by up to 10 cm−1 due to symmetry changes. In addition, some of the Eu lines show splittings of about 4–30 cm−1 as a consequence of the change of the local environment. From the room temperature absorption measurements some of the low energy crystal field levels of 7F and 5D states of the Eu3+ ions
were successfully determined for both modifications.

magyar

Article

PeerReviewed

info:eu-repo/semantics/article

text

http://real.mtak.hu/41009/1/klengyel_2016_OM_open_access.pdf

Lengyel, K. and Beregi, E. and FĂśldvĂĄri, I. and Corradi, G. and KovĂĄcs, L. and Solarz, P. and Ryba-Romanowski, W. (2016) Effect of symmetry reduction on the electronic transitions in polytypic GdAl3(BO3)4:Eu:Tb crystals. OPTICAL MATERIALS, 53. pp. 30-33. ISSN 0925-3467

http://real.mtak.hu/41009/

http://dx.doi.org/10.1016/j.optmat.2016.01.011

10.1016/j.optmat.2016.01.011