Vibrational properties of nonlinear optical Bi2ZnOB2O6 single crystals doped with Pr3+: μ-Raman investigations

Spectroscopic properties of Bi2ZnOB2O6 single crystals doped with Pr3+ ions: Absorption and luminescence investigations

“…If for a particular transition the branching ratio is about or greater than 0.5, such a transition can be considered as a potential lasing transition [44,45]. We also mention here that the gap between the 1 D 2 and 1 G 4 levels is about 7000 cm À1 , and it can be bridged by a few high-energy phonons, whose energies are greater than 1200 cm À1 [15], that can be the reason for the fast decay of the 1 D 2 state.…”

“…Our preliminary investigations show that the Bi 2 ZnOB 2 O 6 crystals may be efficiently doped with the RE ions and can emit in the NIR and VIS spectral ranges; in addition, the second and third harmonic generation (SHG/THG) processes can be also realized. Some spectroscopic and NLO properties of Bi 2 ZnOB 2 O 6 pure and doped with RE ions, were intensively studied by us using different experimental techniques [15,16].…”

“…The local symmetry of the Zn and Bi sites is C 1 ; they are four and six-coordinated by the oxygen atoms, respectively. The oxygen atoms form four types of configurations: three-coordinated BO 3 planar groups (D 3h symmetry); four-coordinated BO 4 tetrahedra (T d symmetry); polyhedra ZnO 4 with four vertices around the Zn atoms and polyhedra BiO 6 with six oxygen atoms around the Bi atoms [15,17] [15]. Rather high phonon frequencies, exceeding or close to 1000 cm À1 , suggest fast non-radiative relaxation, as will be seen below, when the experimental results will be described.…”

Efficient near-infrared quantum cutting by cooperative energy transfer in Bi3TeBO9:Nd3+ phosphors

“…Some of them are Raman-active (l 1 , l 3 , l 4 ) and/or IR-active modes (l 2 , l 3 , l 4 ). The vibrations of an ideal, isolated BO 3 group can be classified into four fundamental modes: symmetric stretching mode l 1 (* 950 cm -1 ), doubly degenerate asymmetric stretching mode l 3 (1250-1400 cm -1 ), doubly degenerate planar bending mode l 4 (* 600 cm -1 ) and infrared active out-ofplane bending mode l 2 (700-800 cm -1 ) [13,32,33]. Moreover, the frequencies of external lattice vibrations (translations or librations of Bi (Nd) or Te atoms and BO 3 and TeO 6 groups) are located below * 350 cm -1 .…”

Synthesis of New Isostructural Orthoborates NaBaR(BO3)2 with R = Tb, Dy, Ho, Er, Tm and Lu

“…The Raman spectra show typical vibration modes of the triangular BO 3 group. It is well known that isolated BO 3 ion with D 3h symmetry characterized by four fundamental modes of which three Raman-active v' 1 (A' 1 ) (~950cm -1 ), v' 3 (E') (~1250-1400 cm -1 ), v' 4 (E' 1 ) (~600 cm -1 ) and one infrared active 13 .…”