A self-starting, passively modelocked figure-8 fiber laser is specifically configured to self-start into a low noise mode by controlling one or more operating parameters of the laser including, but not limited to, the coupling ratio between the uni-directional fiber loop and the bi-directional mirror loop, the accumulated dispersion within the figure-8 structure, and the amount of power present in the laser cavity. A self-starting passive modelocked figure-8 laser may also be made to self-start by initially increasing the pump current above its lasing threshold. Including a band-pass filter in the uni-directional loop has been found to ensure that the laser will enter a low noise lasing mode.

A self-starting, passively modelocked figure-8 fiber laser is specifically configured to self-start into a low noise mode by controlling one or more operating parameters of the laser including, but not limited to, the coupling ratio between the uni-directional fiber loop and the bi-directional mirror loop, the accumulated dispersion within the figure-8 structure, and the amount of power present in the laser cavity. A self-starting passive modelocked figure-8 laser may also be made to self-start by initially increasing the pump current above its lasing threshold. Including a band-pass filter in the uni-directional loop has been found to ensure that the laser will enter a low noise lasing mode.

A rare earth-doped optical fiber comprises a fluorosilicate core surrounded by a silica cladding, where the fluorosilicate core comprises an alkaline-earth fluoro-alumino-silicate glass, such as a strontium fluoro-alumino-silicate glass. The rare earth-doped optical fiber may be useful as a high-power fiber laser and/or fiber amplifier. A method of making a rare earth-doped optical fiber comprises: inserting a powder mixture comprising YbF.sub.3, SrF.sub.2, and Al.sub.2O.sub.3 into a silica tube; after inserting the powder mixture, heating the silica tube to a temperature of at least about 2000 C., some or all of the powder mixture undergoing melting; drawing the silica tube to obtain a reduced-diameter fiber; and cooling the reduced-diameter fiber. Thus, a rare earth-doped optical fiber comprising a fluorosilicate core surrounded by a silica cladding is formed.

An amplifier operable with an electrical drive signal can amplify signal light having a signal wavelength. A laser diode has an active section with input and output facets. An optical isolator is integrated with a package that includes the laser diode. The active section is configured to generate pump light in response to injection of the electrical drive signal into the active section. The pump light has a pump wavelength different from the signal wavelength. A doped fiber doped with an active dopant is in optical communication with the signal light and is in optical communication with at least a portion of the pump light from the laser diode. The pump wavelength of the pump light is configured to interact with the active dopant of the fiber and thereby amplify the signal light.

The present application is applicable to laser technology field and provides a dual-wavelength synchronous pulsed fiber laser based on rare earth ions co-doped fiber, which includes a continuous light LD pumping source, a rare earth ions co-doped fiber and two resonant cavities. Sensitizing ions in the rare earth ions co-doped fiber absorb the pumping light and radiate laser of one wavelength. Meanwhile, sensitized ions in the rare earth ions co-doped fiber radiate laser of another wavelength. Laser generated by sensitizing ions is subjected to Q-switching or mode locking with the saturable absorber inserted in the cavity to generate pulsed laser. Generation and partial reabsorption for the pulsed laser modulates gain of the laser radiated by sensitized ions periodically and generates synchronous pulsed laser, thereby implementing a dual-wavelength synchronous pulsed fiber laser.

A compact laser is provided for in accordance with an exemplary embodiment in the present disclosure includes a compact resonator structure using a non-planar geometry of bulk components. The laser includes a preferred rotational direction of lasing modes and employs bulk components for establishing the preferred rotational direction of lasing modes within resonator. In some embodiments, the preferred rotational direction of lasing modes is established using a reflective element that is outside the resonator structure. In some embodiments, the reflective element induces polarization shifts in the reflected light that are compensated for by a wave plate, which may be outside the resonator structure.

An energy storage capsule for storing energy in the form of photons. The body of the capsule may surround a sealed vacuum environment in which several layers of reactive material are contained, including an inner reflective coating, a first photovoltaic cell, an optical amplification medium, a second photovoltaic cell, and an outer reflective coating, provided in that order. The body of the capsule may also be reflective, for example polished aluminum. Light may be emitted from an LED wafer which may be integrated with the surface of the optical amplification medium, directed at the several layers of reactive material. Some photons may be reflected by the reflective material, storing them within the capsule, while others may be absorbed by the photovoltaic cells, powering the LEDs to transmit more photons. The thermal environment of the energy storage capsule may be maintained such that the LEDs can operate at over 100% efficiency.

An active laser medium for emitting a light beam by laser effect includes an XF2-doped crystal, wherein X is a chemical element from the alkaline-earth family and F is fluorine. The crystal is doped with trivalent ions including: a first category of optically active dopant ions, in which each dopant ion is an ion of a first rare earth; and a second category of optically inactive dopant ions, referred to as buffer ions, in which each dopant ion is an ion of a rare earth different from the first rare earth. The second category of dopant ions has at least ions of a second rare earth and ions of a third rare earth, different from one another. The invention provides an active laser medium that can be used to obtain both a desired emission spectrum shape and a high thermal conductivity.

A Q-switched laser includes a laser cavity including a cavity mirror and an output coupler mirror. The Q-switched laser also includes a doped laser gain material disposed in the laser cavity and a Q-switch including a saturable absorber comprising Fe.sup.2+:ZnSe or Fe.sup.2+:ZnS.

A laser ignition system, in particular for an internal combustion engine, including a vertical emitter and a laser-active crystal, the laser-active crystal being doped in at least some areas using ytterbium, the ytterbium-doped area having a length of 200 m to 7000 m. The monolithic laser is based on a YAG or LuAG host crystal having 3 differently doped areas: a laser-active ytterbium-doped area, an undoped area which determines the resonator length and therefore the pulse duration, and a chromium-doped or vanadium-doped area for the passive Q-switch. The resonator is delimited by 2 mirrors.