Synthesis and determination of the structural and optical characteristics of cBN micropowder with Eu$^{3+}$ ions

Cubic boron-nitride micropowder with Eu$^{3+}$ ions (cBN:Eu) is synthesized under conditions of high pressures and temperatures. The structural, morphological, chemical, and optical characteristics of the cBN:Eu micropowder are studied using X-ray diffraction, energy-dispersive X-ray spectral microanalysis, photoluminescence, and optical transmission methods. It is found that the cBN:Eu lattice parameter is $\sim$ 3.615 $\mathring{\mathrm{A}}$. The intense red luminescence of the cBN:Eu micropowder (red glow), measured in the visible region of the spectrum in the range from 550 to 750 nm, is attributed to intracenter 4$f$-electron transitions of the Eu$^{3+}$ ions. The possible nature of the cBN:Eu micropowder luminescence is discussed.