Crystal oscillators are loosely divided by the frequency they function at and whether or not they are elementary oscillators—work with the frequency marked around the can or at even multiples of that (overtone oscillators). We current a Nd:GdVO4 bulk crystal oscillator with >70 WTEM00 laser output based upon the orthogonal https://www.hxcrystals.com/seokeywords/bulk-crystal-oscillator.html