A fiber laser is configured with a double clad fiber with a core doped with ions of Erbium (Er.sup.+3) and Ytterbium (Yb.sup.+3). At least two spaced apart high and low reflection mirrors flank the core and define a resonant cavity therebetween. The fiber laser further includes a pump laser outputting light in a 1.02-1.06 μm wavelength range which is coupled into the Yb:Er doped double clad fiber.

A fiber amplifier includes a double clad fiber with a core doped with ions of Erbium (Er.sup.+3) and Ytterbium (Yb.sup.+3), and a pump laser generating radiation at a pump wavelength in a 1.02-1.06 wavelength range, a pump laser outputting light in a 1.02-1.06 μm wavelength range coupled into the Yb:Er doped double clad fiber.

The disclosed fiber laser and fiber amplifier each have a significantly higher lasing threshold in the 1 μm wavelength range than the threshold of the known schematics operating at a 9xx nm pump wavelength.

High-power, highly efficient 3-level system fiber lasers are described. The lasers can operate at an average power of about 50W or greater with an efficiency of about 60% or greater with low diffraction limited mode quality. The lasers incorporate an all-solid photonic bandgap fiber that includes a large core (20 micrometers or greater), a high core/clad ratio (greater than 15%), and a waveguide cladding designed to define a transmission band to suppress the 4-level system of the gain medium through determination of the node size of individual nodes of a cladding lattice.

A problem with a conventional waveguide type laser device is that in the case in which an isotropic laser medium is used for a core, linearly polarized light is not provided. A ridge waveguide laser device of the present disclosure includes: a substrate; a core joined to the substrate and having a laser medium, the core having a refractive index higher than that of the substrate; and a cladding joined to the core, constituting a ridge waveguide together with the core, and made from a birefringent material having ordinary and extraordinary refractive indices lower than the refractive index of the core, the ordinary and extraordinary refractive indices being different.

A solid state ring laser gyroscope comprises a laser block including a resonant ring cavity having an optical closed loop pathway; a plurality of mirror structures mounted on the block and including respective multilayer mirrors that reflect light beams around the closed loop pathway; and a pump laser assembly in optical communication with the closed loop pathway through one of the mirror structures. One or more of the multilayer mirrors includes a rare-earth doped gain layer operative to produce bidirectional optical amplification of counter-propagating light beams in the closed loop pathway. In some embodiments, the gain layer comprises a rare-earth dopant other than neodymium that is doped into a glassy host material comprising titania, tantalum oxide, alumina, zirconia, silicate glass, phosphate glass, tellurite glass, fluorosilicate glass, or non-oxide glass. Alternatively, the gain layer can comprise a neodymium dopant that is doped into a glassy host material other than silica.

A laser device is provided that includes an element made of laser-active material and a cladding element bonded to the element so as to allow heat exchange by heat conduction between the cladding element and the element. The laser-active material emitting laser light when excited by pump light. The element being made of a glass. The cladding element being made of a material that exhibits an absorption coefficient for the pump light that is lower than a corresponding absorption coefficient of the glass. The element and cladding element being configured so that the pump light can be directed through the cladding element into the element and/or so that the pump light can be directed through the element into the cladding element.

High-power, highly efficient 3-level system fiber lasers are described. The lasers can operate at an average power of about 50W or greater with an efficiency of about 60% or greater with low diffraction limited mode quality. The lasers incorporate an all-solid photonic bandgap fiber that includes a large core (20 micrometers or greater), a high core/clad ratio (greater than 15%), and a waveguide cladding designed to define a transmission band to suppress the 4-level system of the gain medium through determination of the node size of individual nodes of a cladding lattice.

A solid state ring laser gyroscope comprises a laser block including a resonant ring cavity having an optical closed loop pathway; a plurality of mirror structures mounted on the block and including respective multilayer mirrors that reflect light beams around the closed loop pathway; and a pump laser assembly in optical communication with the closed loop pathway through one of the mirror structures. One or more of the multilayer mirrors includes a rare-earth doped gain layer operative to produce bidirectional optical amplification of counter-propagating light beams in the closed loop pathway. In some embodiments, the gain layer comprises a rare-earth dopant other than neodymium that is doped into a glassy host material comprising titania, tantalum oxide, alumina, zirconia, silicate glass, phosphate glass, tellurite glass, fluorosilicate glass, or non-oxide glass. Alternatively, the gain layer can comprise a neodymium dopant that is doped into a glassy host material other than silica.

A laser amplifier includes a volume configured to receive pump light from an array of laser diodes pump source, and a gain medium arranged within the volume and configured to amplify light in response to receiving the pump light. The gain medium comprises a first solid-state element configured to emit a first laser radiation having a peak centered at a first peak fluorescence wavelength and a second solid-state element configured to emit a second laser radiation having a peak centered at a second peak fluorescence wavelength. Each of the first and the second solid-state elements contain respective active laser ions. The difference between the first peak fluorescence wavelength and the second peak fluorescence wavelength is larger than or equal to 10 nm and smaller than or equal to 60 nm. The first solid-state element and the second solid-state element are cooled, for instance fluid-cooled.

A laser medium, for generating laser light, that includes a light exit surface through which the laser light exits from the laser medium during laser operation. The light exit surface has a boundary which is defined by at least one chamfer or groove.

The passively q-switched diode end-pumped solid-state laser is used the gain medium made of Er:Yb doped crystal and the Q-switch made of Co.sup.2+:MgAl.sub.2O.sub.4 crystal. The optical elements are optimally designed for the resonator to achieve pulse energy in a range 0.5 mJ?E?2 mJ with the pulse width in a range of 4 ns-15 ns. The resonator is appropriate to use in laser rangefinders, target designator, and other products in military and civilian applications.