An active laser medium for emitting a light beam by laser effect includes an X—F2-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.

An optical amplifier comprises a gain medium having an input surface and an output surface wherein the output surface is larger than the input surface. The gain medium may be frustum shaped. The optical amplifier includes a negative diverging lens to receive an extraction laser beam and to cause the laser beam to expand as the beam passes through the gain medium. The amplifier further comprises a positive collimating lens configured to receive the expanding amplified beam and reduce the divergence. The gain medium can be pumped by counter-propagating radiation. The fluence of the laser beam within the gain medium is configured to be near constant along the length of the gain medium and may be within 1.5-2.0 F.sub.SAT. The gain medium may be doped with dopant to provide gain, with larger concentration of dopants proximal the input surface and smaller concentration proximal the output surface.

The present application is directed to various architectures of a laser oscillator which include an optical element, reflective, refractive, or diffractive injection device for injection seeding and/or locking a laser oscillator.

A high-power mode-locked laser system is disclosed herein which includes at least one pump source, at least one laser cavity formed by at least one high reflector and at least one output coupler, and at least one ytterbium-doped optical crystal positioned within the laser cavity in communication with the pump source, the ytterbium-doped optical crystal configured to output at least one output signal of at least 20 W, having a pulse width of 200 fs or less, and a repetition rate of at least 40 MHz.

A high-power ytterbium-doped calcium fluoride laser system is disclosed herein which includes at least one pump source, at least one laser cavity formed by at least one high reflector and at least one output coupler, and at least one ytterbium-doped calcium fluoride optical crystal positioned within the laser cavity in communication with the pump source, the ytterbium-doped calcium fluoride optical crystal configured to output at least one output signal of at least 20 W, having a pulse width of 200 fs or less, and a repetition rate of at least 40 MHz.

The present application discloses a double-clad crystal fiber which includes a Yb-doped CALGO core region, a pump cladding region configured to have the core region positioned therein, and a second cladding region configured to have the core region and pump cladding region positioned therein.

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 divided-pulse laser regeneration amplification apparatus includes: a signal light coupling component including a first half-wave plate, a first polarization beam splitter, a first Faraday rotator and a second half-wave plate placed in sequence; and a divided-pulse laser regeneration amplification component including a second polarization beam splitter and a third reflector, the second polarization beam splitter is adjacent to the second half-wave plate and is in a same column as the third reflector and the second half-wave plate; a first quarter-wave plate, a Pockels cell and a first reflector are successively arranged on a first side of the second polarization beam splitter, and a third half-wave plate, a first pulse polarization separation component and a first non-linear pulse amplification component are successively arranged on a second side of the second polarization beam splitter.

A solid-state laser system may include: a solid-state laser unit configured to output first pulsed laser light with a first wavelength and second pulsed laser light with a second wavelength; a first solid-state amplifier configured to receive the first pulsed laser light, and output third pulsed laser light with the first wavelength; a wavelength converter configured to receive the third pulsed laser light, and output harmonic light with a third wavelength; a second solid-state amplifier configured to receive the second pulsed laser light, and output fourth pulsed laser light with the second wavelength; a Raman laser unit configured to receive the fourth pulsed laser light, and output Stokes light with a fourth wavelength; and a wavelength conversion system configured to receive the harmonic light and the Stokes light, and output fifth pulsed laser light with a fifth wavelength converted in wavelength from the third wavelength and the fourth wavelength.

A solid-state laser system may include: a solid-state laser unit configured to output first pulsed laser light with a first wavelength and second pulsed laser light with a second wavelength; a first solid-state amplifier configured to receive the first pulsed laser light, and output third pulsed laser light with the first wavelength; a wavelength converter configured to receive the third pulsed laser light, and output harmonic light with a third wavelength; a second solid-state amplifier configured to receive the second pulsed laser light, and output fourth pulsed laser light with the second wavelength; a Raman laser unit configured to receive the fourth pulsed laser light, and output Stokes light with a fourth wavelength; and a wavelength conversion system configured to receive the harmonic light and the Stokes light, and output fifth pulsed laser light with a fifth wavelength converted in wavelength from the third wavelength and the fourth wavelength.