A multi-clad optical fiber design is described in order to provide low optical loss, a high numerical aperture (NA), and high optical gain for the fundamental propagating mode, the linearly polarized (LP) 01 mode in the UV and visible portion of the optical spectrum. The optical fiber design may contain dopants in order to simultaneously increase the optical gain in the core region while avoiding additional losses during the fiber fabrication process. The optical fiber design may incorporate rare-earth dopants for efficient lasing. Additionally, the modal characteristics of the propagating modes in the optical core promote highly efficient nonlinear mixing, providing for a high beam quality (M.sup.2<1.5) output of the emitted light.

A mid-infrared cascading fiber amplifier device having a source configured to generate a first electromagnetic wave output at a first frequency, a fiber coupled to the source and a pump coupled to the fiber and configured to generate a second electromagnetic wave output at a second frequency, wherein the second frequency is higher than the first frequency and causes the fiber to undergo two or more transitions in response to stimulation by the first electromagnetic wave output at the first frequency, wherein the first transition generates the first electromagnetic wave output approximately at the first frequency and the second transition generates the first electromagnetic wave output approximately at the first frequency.

A solid-state optical amplifier is described, having an active core and doped cladding in a single chip. An active optical core runs through a doped cladding in a structure formed on a substrate. A light emitting structure, such as an LED, is formed within and/or adjacent to the optical core. The cladding is doped, for example, with erbium or other rare-earth elements or metals. Several exemplary devices and methods of their formation are given.

A mid-infrared cascading fiber amplifier device having a source configured to generate a first electromagnetic wave output at a first frequency, a fiber coupled to the source and a pump coupled to the fiber and configured to generate a second electromagnetic wave output at a second frequency, wherein the second frequency is higher than the first frequency and causes the fiber to undergo two or more transitions in response to stimulation by the first electromagnetic wave output at the first frequency, wherein the first transition generates the first electromagnetic wave output approximately at the first frequency and the second transition generates the first electromagnetic wave output approximately at the first frequency.

The invention provides a light generating system (1000) comprising (a) first light generating device (110), (b) a first laser (2100), and (c) a second laser (2200), wherein:the first light generating device (110) is configured to generate first device light (111) having a first device centroid wavelength (.sub.cd,1), wherein the first light generating device (110) comprises one or more of a solid state material laser and a super luminescent diode; the first laser (2100) comprises a first lanthanide based luminescent material (2110) configured to convert at least part of the first device light (111) having the first device centroid wavelength (.sub.cd,1) into first luminescent material light (2111), wherein the first laser (2100) is configured downstream of the first light generating device (110) and is configured to provide first laser light (2101) comprising at least part of the first luminescent material light (2111), wherein the first laser light (2101) has a first centroid laser wavelength (.sub.cl,1) in the visible; the second laser (2200) comprises a second lanthanide based luminescent material (2210) configured to convert at least part of the first device light (111) having the first device centroid wavelength (.sub.cd,1) into second luminescent material light (2211), wherein the second laser (2200) is configured downstream of the first light generating device (110) and is configured to provide second laser light (2201) comprising at least part of the second luminescent material light (2211), wherein the second laser light (2201) has a second centroid laser wavelength (.sub.cl,2) in the visible, wherein |.sub.cl,2.sub.cl,1|25 nm; the first centroid laser wavelength (.sub.cl,1) and the second centroid laser wavelength (.sub.cl,2) are selected from different wavelength ranges from C the group of (i) 495-570 nm, (ii) 570-590 nm, (iii) 590-620 nm, and (iv) 620-780 nm, andin a first operational mode of the light generating system (1000) the light generating system (1000) is configured to provide system light (1001) comprising the first laser light (2101) and the second laser light (2201), and wherein in the first operational mode the system light (1001) is white light.

A laser apparatus includes: a laser oscillator that includes a mirror and emits a laser beam; and an external resonator that includes a nonlinear optical crystal that functions as a phase conjugate mirror. The phase conjugate mirror reflects the laser beam and produces a phase conjugate wave that reaches the mirror of the laser oscillator, and the mirror of the laser oscillator and the phase conjugate mirror cause laser oscillation such that a wavelength and a phase of the laser beam oscillated by the laser oscillation are automatically fixed.

The present invention provides an apparatus and method for pumping solid-state lasers and amplifiers. More specifically, to a method and apparatus for pumping solid-state lasers and amplifiers using Light Emitting Diode (LED) arrays. In one embodiment, the apparatus comprises a gain medium, a plurality of LEDs in optical communication with the gain medium to excite the gain medium, the plurality of LEDs arranged in an LED array, a driving circuit to energize the LED array, and a thermoelectric cooler to reduce the temperature of the LED array, wherein the gain medium is pumped by the LED array to emit a laser light.

A cascaded slow light amplifier and a system comprising such amplifier is described. The amplifier includes a unit wherein each unit comprising of at least one host crystal doped with ions and optically prepared to provide at least one amplification

An optical device comprises a Praseodymium (Pr)-dope waveguide optical amplifier capable of amplifying O-band light. The waveguide optical amplifier may be formed on the substrate (e.g., silicone or glass) and comprises a core defining an optical path through the waveguide optical amplifier, and cladding abutting at least one side of the core. The core comprises a silicon-based material, such as silicon nitride (Si.sub.3N.sub.4), doped with Praseodymium (Pr) such that, on condition of pump light and O-band signal light being passed through the waveguide optical amplifier, the waveguide optical amplifier amplifies the O-band signal light.

A visible laser or laser amplifier is provided with a ceramic gain medium having a uniaxial anisotropic scattering property such that scattering losses for a visible laser beam along one axis are lower than that along perpendicular axes, and that axis is used as the optical path. The ceramic gain medium includes at least a trivalent praseodymium dopant (Pr.sup.3+) within a host body based on CaF.sub.2, SrF.sub.2, BaF.sub.2, or a solid solution thereof. Co-dopants can include one or more other trivalent rare earth (RE) elements chosen from Lu.sup.3+, Y.sup.3+, Gd.sup.3+, and La.sup.3+. The ceramic gain medium, which is made from wet-chemistry precipitated powders, undergoes uniaxial compression, generally under high heat, as an essential step in its manufacture. In use, a pump source using a laser diode of gallium nitride-based semiconductor can be advantageously paired with the gain medium.