Abstract: A process of transferring a layer of a first material from a first substrate, having defects in a zone close to the surface, onto a host substrate made of a second material includes a step of thinning the first substrate in order to form a first thinned substrate, an ion or atom implantation in the first substrate in order to form an implantation plane therein, delimiting the layer to be transferred, and a transfer of the layer onto the host substrate by fracturing the substrate along the implantation plane.

Abstract: Method of producing a partly or completely semi-insulating or p-type doped ZnO substrate from an n-type doped ZnO substrate, in which the n-type doped ZnO substrate is brought into contact with an anhydrous molten salt chosen from anhydrous molten sodium nitrate, lithium nitrate, potassium nitrate and rubidium nitrate. Partly or completely semi-insulating or p-type doped ZnO substrate, said substrate being in particular in the form of a thin layer, film or in the form of nanowires; and said substrate being doped at the same time by an element chosen from Na, Li, K and Rb; by N; and by O; it being furthermore possible for ZnO or GaN to be epitaxially grown on this substrate. Electronic, optoelectronic or electro-optic device such as a light-emitting diode (LED) comprising this substrate.

Abstract: A method for preparing polycrystalline or single-crystal zinc oxide ZnO on a seed placed in an enclosure under a controlled atmosphere, by sublimation of a zinc oxide source placed in a crucible inside the enclosure and distant from the seed, by formation of gas species, transport of gas species, condensation of gas species on the seed, recombination of the ZnO at the surface of the seed, growth of polycrystalline or single-crystal ZnO on the seed, and cooling of the polycrystalline or single-crystal ZnO, wherein: the zinc oxide source is heated by induction at a temperature, a so-called sublimation temperature, from 900 to 1,400° C. under a pressure from 2.10?3 atmospheres to 0.

Abstract: Method of producing a partly or completely semi-insulating or p-type doped ZnO substrate from an n-type doped ZnO substrate, in which the n-type doped ZnO substrate is brought into contact with an anhydrous molten salt chosen from anhydrous molten sodium nitrate, lithium nitrate, potassium nitrate and rubidium nitrate. Partly or completely semi-insulating or p-type doped ZnO substrate, said substrate being in particular in the form of a thin layer, film or in the form of nanowires ; and said substrate being doped at the same time by an element chosen from Na, Li, K and Rb; by N; and by O; it being furthermore possible for ZnO or GaN to be epitaxially grown on this substrate. Electronic, optoelectronic or electro-optic device such as a light-emitting diode (LED) comprising this substrate.

Abstract: A process of transferring a layer of a first material from a first substrate, having defects in a zone close to the surface, onto a host substrate made of a second material includes a step of thinning the first substrate in order to form a first thinned substrate, an ion or atom implantation in the first substrate in order to form an implantation plane therein, delimiting the layer to be transferred, and a transfer of the layer onto the host substrate by fracturing the substrate along the implantation plane.

Abstract: Mixed lathanum-magnesium aluminates, their production process and lasers using these aluminates.These lasers comprise two flash lamps for longitudinally pumping a bar of an aluminate of formula La.sub.1-x Nd.sub.x Mg.sub.Y Al.sub.11 O.sub.18+y, x and y being numbers such that O<x.ltoreq.0.2 and O<y<1, preferably with y ranging from 0.5 to 0.55, emitting in the infrared, mirrors for amplifying the light emitted by the bar and a polarizing prism for passing the amplified light beam outside the laser.

Abstract: These lasers in particular have two flashlamps (30, 32) for longitudinally pumping a monocrystalline aluminate bar (28) emitting in the visible and near infrared, two mirrors (38, 40) for amplifying the light emitted by the bath, a polarizer prism (42) used for feeding the amplified light beam to the outside of the laser cavity. The magnetoplumbite-type aluminate has in particular the formula:La.sub.1-x Mg.sub.1-y-z Mt.sub.v Al.sub.11+x+2y/ 3-v O.sub.19-z(II)in which Mt represents a transition metal chosen from titanium and zirconium; x is a number such that 0<x<0.3; y and z are numbers such that 0.ltoreq.y+z.ltoreq.1 with 0.ltoreq.y.ltoreq.1 and 0.ltoreq.z.ltoreq.1; v is a number such that 0<v<1.