Abstract: A fiber amplifier for amplifying an optical signal, comprising a pump energy source capable of emitting energy at a pump wavelength: optical apparatus for transmitting the optical signal, the optical apparatus having a plurality of discrete portions, each discrete portion comprising a length of optical fiber and first and second components disposed at first and second respective locations and configured to substantially prevent energy having an intermediate wavelength in the discrete portion from entering other discrete portions of the optical apparatus; and a plurality of waveguides, each waveguide coupled to the pump energy source and to one of the plurality of discrete portions, each waveguide for providing energy at the pump wavelength from the pump energy source to its corresponding discrete portion, thereby increasing an intensity of light at the discrete portion's intermediate wavelength.

Abstract: The invention features a fiber that includes an optical fiber (110) containing a gain medium having a Raman active material with a Raman gain spectrum. The optical fiber is configured to receive energy at a wavelength ?p. The fiber also includes at least three pairs of reflectors (120, 125, 150, 130, 160) disposed in the optical fiber. Each pair of reflectors forms a resonance cavity (140) with a resonance frequency.

Abstract: Optical fibers (e.g., fiber amplifiers and fiber lasers), and systems containing optical fibers (e.g., fiber amplifier systems and fiber laser systems) are disclosed.

Abstract: Fiber laser systems. One system comprises a pump energy source, a first fiber and a WDM for transferring pump energy from the first fiber to a second fiber that comprises a grating for reflecting energy at a predetermined wavelength. The first fiber is devoid of a grating substantially reflecting energy of the predetermined wavelength. In another embodiment, a system includes a pump energy source and a fiber comprising a loop-shaped portion, a first non loop-shaped portion comprising a grating for reflecting pump energy, and a second non loop-shaped portion comprising a grating for reflecting a Stoke shifted wavelength.

Abstract: Optical fibers (e.g., fiber lasers and fiber amplifiers), and systems containing such optical fibers are disclosed.

Abstract: The invention features a fiber that includes an optical fiber (110) containing a gain medium having a Raman active material with a Raman gain spectrum. The optical fiber is configured to receive energy at a wavelength &lgr;p. The fiber also includes at least three pairs of reflectors (120, 125, 150, 130, 160) disposed in the optical fiber. Each pair of reflectors forms a resonance cavity (140) with a resonance frequency.

Abstract: Optical fibers (e.g., fiber amplifiers and fiber lasers), and systems containing optical fibers (e.g., fiber amplifier systems and fiber laser systems) are disclosed.

Abstract: Raman fiber lasers and systems including Raman fiber lasers are disclosed.