A device is described herein which may comprise an optical amplifier having a gain band including wavelengths lambda1 and lambda2, with lambda1 not equal to lambda2; a pre-pulse seed laser having a tuning module for tuning a pre-pulse output to wavelength lambda1; a main pulse seed laser generating a laser output having wavelength, lambda2; and a beam combiner for directing the pre-pulse output and the main pulse output on a common path through the optical amplifier.