| Abstract: | A laser apparatus includes a plurality of pumps each of which is
configured to emit a corresponding pump laser beam having a unique peak
wavelength. The laser apparatus includes a spectral beam combiner
configured to combine the corresponding pump laser beams into a
substantially spatially-coherent pump laser beam having a pump spectrum
that includes the unique peak wavelengths, and first and second
selectively reflective elements spaced from each other to define a lasing
cavity including a lasing medium therein. The lasing medium generates a
plurality of gain spectra responsive to absorbing the pump laser beam.
Each gain spectrum corresponds to a respective one of the unique peak
wavelengths of the substantially spatially-coherent pump laser beam and
partially overlaps with all other ones of the gain spectra. The
reflective elements are configured to promote emission of a laser beam
from the lasing medium with a peak wavelength common to each gain
spectrum. |