Abstract: The invention is related to nuclear physics, medicine and oil industry, namely to the measurement of x-ray, gamma and alpha radiation; control for trans uranium nuclides in the habitat of a man; non destructive control for the structure of heavy bodies; three dimensional positron-electron computer tomography, etc. The essence of the invention is in additional ingredients in a chemical composition of a scintillating material based on crystals of oxyorthosilicates, including cerium Ce and crystallized in a structural type Lu2SiO5.

Abstract: Quantum electronics are useful for materials for laser technique for use in solid state lasers with emitting wavelength of between 2.8 and 3.1 .mu.m. It has been found possible to raise the gain of laser material, to lower the stimulation threshold for generation, to increase the generation efficiency, and to widen the available range of the industrial generating systems with continuously variable emission wavelengths in the range 2.8 -3.1 .mu.m, including those operating in short-pulse generation and amplification modes. It is also possible to prevent fissures forming in the crystal, to reduce scattering, to improve radiation durability, to decrease dissipation, and to reduce passive absorption. The laser material has a garnet structure and contains between 0.025 formula units (f.u.) And 2.95 f.u. of holmium and in addition at least one of the following elements: Li, Be, B, Na, Ca, Mg, Si, K, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Ge, Rb, Sr, Zr, Nb, Mo, W, Ta, Hf, and Bi in quantities of between 1.times.10.sup.