Abstract: An optical source having a fiber emitting controlled single-transverse mode radiation at a wavelength of less than 1030 nm, includes at least one laser diode suitable for emitting a pumping wave; and a section of sheathed amplifying optical fiber having two ends, the amplifying optical fiber comprising a core and a pumping sheath, the fiber being doped with a rare earth dopant; a device for coupling the pumping source in the sheath of the doped fiber, characterized in that the core of the doped fiber includes a cylindrical portion doped with a rare earth element selected among ytterbium, neodymium, and thulium, in order to obtain a refractive index of the core that is higher than the refractive index of the sheath; the excitation wavelength of the laser diode is between 750 nm and 960 nm; the diameter of the sheath is greater than 50 microns, and the surface ratio of the doped core to the pumping sheath is between 8 and 50.

Abstract: An optical source having a fiber emitting controlled single-transverse mode radiation at a wavelength of less than 1030 nm, includes at least one laser diode suitable for emitting a pumping wave; and a section of sheathed amplifying optical fiber having two ends, the amplifying optical fiber comprising a core and a pumping sheath, the fiber being doped with a rare earth dopant; a device for coupling the pumping source in the sheath of the doped fiber, characterized in that the core of the doped fiber includes a cylindrical portion doped with a rare earth element selected among ytterbium, neodymium, and thulium, in order to obtain a refractive index of the core that is higher than the refractive index of the sheath; the excitation wavelength of the laser diode is between 750 nm and 960 nm; the diameter of the sheath is greater than 50 microns, and the surface ratio of the doped core to the pumping sheath is between 8 and 50.

Abstract: The present invention generally relates to coherent, ultra-short ultraviolet (UV) or extended ultraviolet (XUV) pulse generation, and more particularly, to a highly bright re-focusable source capable of producing, at an adjustable rate comprised between 50 kHz and a few megahertz, femtosecond long pulses, in the ultraviolet or extended ultraviolet range. It comprises: —a fiber laser device adapted to produce laser beam comprising pulses, —an harmonic generator device comprising an interaction medium. The harmonic generator device and the fiber laser device are coupled so that the laser beam hits the interaction medium with a power of at least 10 13 W/cm2, so as to generate said UV-XUV pulses.

Abstract: The disclosure relates to a laser device having a fibre emitting a single-mode transverse radiation controlled at a given wavelength, which includes: at least one laser diode capable of emitting a pump wave and a sheathed amplifying optic-fibre segment having two ends, the amplifying optic fibre including a core and a pumping sheath, the fibre being doped with a rare-earth dopant, wherein the core of the fibre has a diameter of between 12 ?m and 200 ?m, and in that the device includes: a coupling means for coupling the pump wave in the pumping sheath to at least one end of the fibre, and a resonator capable of re-injecting a laser beam at the given wavelength at the two ends of said segment, said resonator including an intra-cavity wavelength selective means capable of interaction with the injection means so as to perform a filtration on the given wavelength and re-inject into the fibre the pump wave which has not been absorbed after passing in the fibre.