Abstract: A method for generating amplified laser radiation includes generating a forward-propagating laser beam in a first waveguiding gain stage, amplifying the forward-propagating laser beam in a second waveguiding gain stage, and directing the forward-propagating laser beam from an output waveguide of the first waveguiding gain stage to an input waveguide of the second waveguiding gain stage via a propagation path passing through a Kerr medium. The Kerr medium suppresses coupling, between the first and second waveguiding gain stages, of high-peak-power laser radiation exceeding a threshold intensity in the Kerr medium. Self-focusing in the Kerr medium causes a majority of the high-peak-power laser radiation to be outside at least one of an acceptance aperture and an acceptance angle of a receiving one of the output waveguide of the first waveguiding gain stage and the input waveguide of the second waveguiding gain stage. Each waveguiding gain stage may include a gain fiber.

Abstract: An optical isolator for use with high power, collimated laser radiation includes an input polarizing optical element, at least one Faraday optical element, at least two reflective optical elements for reflecting laser radiation to provide an even number of passes through said at least one Faraday optical element, at least one reciprocal polarization altering optical element, an output polarizing optical element, at least one light redirecting element for remotely dissipating isolated or lost laser radiation. The isolator also includes at least one magnetic structure capable of generating a uniform magnetic field within the Faraday optical element which is aligned to the path of the collimated laser radiation and a mechanical structure for holding said optical elements to provide thermal gradients that are aligned to the path of the collimated laser radiation and that provide thermal and mechanical isolation between the magnetic structure and the optical elements.

Abstract: An optical isolator for generally collimated laser radiation includes a single polarizing element, at least one Faraday optical element, at least one reciprocal polarization altering optical element disposed at the single polarizing element, at least one reflective optical element for reflecting radiation to provide an even number of passes through the at least one Faraday optical element, and a magnetic structure. The magnetic structure is capable of generating a magnetic field within the at least one Faraday optical element that is generally aligned with the even number of passes along a beam propagation axis. The optical isolator is configured to receive generally collimated laser radiation, which passes through the single polarizing element and the at least one reciprocal polarization altering optical element and which makes at least two passes through the at least one Faraday optical element, whereby generally collimated laser radiation is output from the optical isolator.

Abstract: An optical isolator for generally collimated laser radiation includes a single polarizing element, at least one Faraday optical element, at least one reciprocal polarization altering optical element disposed at the single polarizing element, at least one reflective optical element for reflecting radiation to provide an even number of passes through the at least one Faraday optical element, and a magnetic structure. The magnetic structure is capable of generating a magnetic field within the at least one Faraday optical element that is generally aligned with the even number of passes along a beam propagation axis. The optical isolator is configured to receive generally collimated laser radiation, which passes through the single polarizing element and the at least one reciprocal polarization altering optical element and which makes at least two passes through the at least one Faraday optical element, whereby generally collimated laser radiation is output from the optical isolator.

Abstract: An optical isolator for use with high power, collimated laser radiation includes an input polarizing optical element, at least one Faraday optical element, at least two reflective optical elements for reflecting laser radiation to provide an even number of passes through said at least one Faraday optical element, at least one reciprocal polarization altering optical element, an output polarizing optical element, at least one light redirecting element for remotely dissipating isolated or lost laser radiation. The isolator also includes at least one magnetic structure capable of generating a uniform magnetic field within the Faraday optical element which is aligned to the path of the collimated laser radiation and a mechanical structure for holding said optical elements to provide thermal gradients that are aligned to the path of the collimated laser radiation and that provide thermal and mechanical isolation between the magnetic structure and the optical elements.