Highly efficient Nd:YVO4 laser by direct in-band diode pumping at 914 nm

A Nd: YVO4 crystal was pumped directly into the emitting level by a laser diode at 914 nm for the first time to our knowledge. We achieved an output power of 11.5 W at 1064 nm for an absorbed pump power of 14.6 W, corresponding to an optical efficiency of 78.7%. We demonstrated that thermal effects are very weak, in agreement with the low quantum defect of only 14.1%. (C) 2009 Optical Society of America