Investigation of Cr3+ ions in Cs2NaGaF6 single crystals by optical spectroscopy

Magnetic resonance study of Cr 3+ and Fe 3+ centers in hexagonal Cs 2 NaAlF 6 and Cs 2 NaGaF 6 crystals

“…Cs 2 NaAlF 6 and Cs 2 NaGaF 6 crystals, doped with approximately 0.1 atomic % Cr 3+ , were hydrothermally grown [4,5]. X (9.57 GHz) and Q-band (34.0 GHz) EPR and ENDOR spectra were recorded at 20 K on a Bruker ESP300E spectrometer with ESP353 ENDOR/Triple extension, and a Bruker ELEXSYS E500 spectrometer, respectively.…”

“…The hexagonal elpasolite crystals Cs 2 NaMF 6 (M = Al, Ga) are in this respect particularly interesting, because they allow high Cr 3+ doping concentrations. Previous optical [4,5] and electron paramagnetic resonance (EPR) [6,7] studies have shown that Cr 3+ can be incorporated on two crystallographic positions in hexagonal Cs 2 NaMF 6 lattices, which have been proposed to correspond to the two inequivalent M 3+ sites [8,9], shown in Fig. 1.…”

“…Taking into account these data concerning the hexagonal elpasolite structure assignations of optical and EPR spectra for two types of Cr 3+ centers in these crystals have been made. As the luminescence lifetime is expected to decrease when the deviation from cubic symmetry increases, the centers with the shorter luminescence lifetime have been identified as Cr 3+ at position M2 [4,5]. The magnitude of the zero field splitting, which is also a measure for the deviation from cubic symmetry, has been used for assigning the EPR spectra [6,7].…”

Emission spectra of lanthanide ions in hexafluoroelpasolite lattices excited by synchrotron radiation

“…[4]. The crystallographic details for the host lattices are available [15][16][17]. All compounds have a cubic elpasolite-type structure and crystallize in the space group Fm3m, except for Cs 2 NaGaF 6 which has the rhombohedral 12L-type crystal structure and belongs to the space group R-3m.…”

Phonon coupling of Cr3+ ions in Cs2NaAlF6 crystals

“…Cr 3þ ion in fluoride crystals have been investigated by several research groups [6,7] since laser action in KZnF 3 :Cr 3þ was obtained for the first time [8].…”