Growth, Structure, Thermal Properties and Spectroscopic Characteristics of Nd3+-Doped KGdP4O12 Crystal

Abstract

A single crystal of Nd3+-doped KGdP4O12 was successfully grown with the top-seeded solution growth and slow cooling (TSSG−SC) technique. It crystallizes in space group C2/c with cell parameters a = 7.812(2) Å, b = 12.307(3) Å, c = 10.474(2) Å, β = 110.84(3)° and Z = 4. The IR and Raman spectra also indicated that the phosphoric polyhedra of Nd:KGdP4O12 has a cyclic symmetry. The chemical composition of the crystal was analyzed and the distribution coefficient of Nd3+ was calculated. The crystal morphology of KGdP4O12 was identified using X-ray diffraction. The compound has good thermal stability to 920°C. Its specific heat and thermal conductivity were determined for potential applications. The spectral properties of Nd:KGdP4O12 indicates that it exhibits broad absorption and emission bands, which are attributed to low symmetry of the crystal. The broad absorption band around 798 nm has a full-width at half-maximum (FWHM) of 14.8 nm and is suitable for AlGaAs laser diode pumping. Moreover, 5 at% Nd3+-doped KGdP4O12 crystal has a long luminescence lifetime of 300 μs and a high quantum efficiency of 96%.

Structural Study of Europium Doped Gadolinium Polyphosphates LiGd(PO3)4 and Its Effect on Their Spectroscopic, Thermal, Magnetic, and Optical Properties

“…The comparison of spectra (Figure 4) and those obtained in previous works in literature for condensed polyphosphates [30, 31] proves that positions of infrared absorption bands are characteristic of phosphates with chain structures.…”

Crystal growth and optical characteristics of beryllium-free polyphosphate, KLa(PO3)4, a possible deep-ultraviolet nonlinear optical crystal

“…They are due to the different positions of lanthanum and potassium ions giving different frequencies of the ν s (P−O−P)30. For the ν s (P−O−P) of cyclotetraphosphate, there is only one strong peak in the same region31. As such, the Raman double peaks around 700 cm −1 can also be used to identify the structural type of alkali-metal lanthanide metaphosphate.…”

Growth and properties of a noncentrosymmetric polyphosphate CsLa(PO3)4crystal with deep-ultraviolet transparency

“…The title compound, CsLaIJPO 3 ) 4 , belongs to the double phosphates of alkali and lanthanide ions with the general formula ALn(PO 3 ) 4 , which have been studied extensively for potential applications in laser technology, catalysis, electricity and optics. [24][25][26][27][28] CsLa(PO 3 ) 4 crystallizes in the noncentrosymmetric point group C2 and features a 1D [PO 3 ] ∞ helical chain just as in RbBa 2 (PO 3 ) 5 , the recently reported deep-UV NLO crystal. 29 It is well known that alkaline and alkaline-earth cations have a short absorption edge.…”