Abstract: Radiation from a VBG-locked diode-laser at a locked wavelength of 878.6 nm is focused into a 30-mm long Nd:YVO4 optical amplifier crystal for optically pumping the crystal (24). The crystal amplifies a beam of seed-pulses from a fiber MOPA (12). The power of pump radiation is about 75 Watts. The radiation is focused into a beam-waist having a minimum diameter of about 600 micrometers. This provides an amplifier having a high gain-factor well over 100. The high-gain factor provides a gain-shaping effect on the seed-pulse beam which overcomes thermal aberrations inherent in such high-power pumping, thereby producing an amplified seed-pulse beam with M2 less than 1.3.

Abstract: Radiation from a VBG-locked diode-laser at a locked wavelength of 878.6 nm is focused into a 30-mm long Nd:YVO4 optical amplifier crystal for optically pumping the crystal (24). The crystal amplifies a beam of seed-pulses from a fiber MOPA (12). The power of pump radiation is about 75 Watts. The radiation is focused into a beam-waist having a minimum diameter of about 600 micrometers. This provides an amplifier having a high gain-factor well over 100. The high-gain factor provides a gain-shaping effect on the seed-pulse beam which overcomes thermal aberrations inherent in such high-power pumping, thereby producing an amplified seed-pulse beam with M2 less than 1.3.

Abstract: In a first embodiment, the invention makes use of a Neodymium doped YAG (Nd:YAG) gain medium placed in an optical resonant cavity formed by two mirrors. Power extraction is maximized for a specific laser cavity. In particular the concave curvature on the rod ends contributes a negative lensing component to modify the strength of the thermal lens. In a second embodiment the present invention uses an amplifier rod medium with curved ends to act as lensing elements to collect emission from the laser gain medium and/or oscillator described in the first embodiment of the invention. The combination of thermal lens and curved rod ends produces a lensing effect which allows light to be directly coupled from a laser. In addition, variation of the input pump power allows for control of the thermal lens formed within the amplifier rod.

Abstract: In a first embodiment, the invention makes use of a Neodymium doped YAG (Nd: YAG) gain medium placed in an optical resonant cavity formed by two mirrors. Power extraction is maximized for a specific laser cavity. In particular the concave curvature on the rod ends contributes a negative lensing component to modify the strength of the thermal lens. In a second embodiment the present invention uses an amplifier rod medium with curved ends to act as lensing elements to collect emission from the laser gain medium and/or oscillator described in the first embodiment of the invention. The combination of thermal lens and curved rod ends produces a lensing effect which allows light to be directly coupled from a laser. In addition, variation of the input pump power allows for control of the thermal lens formed within the amplifier rod.