An　asymmetric　large　optical　cavity　(LOC)　waveguide　is　designed　to　raise　the　output　power　of　the　940　nm　laser　diode.　By　optimizing　the　metal　organic　chemical　vapor　deposition　growth　condition　and　combining　with　the　electrode　fabrication　and　facet　coating,　single　emitter　semiconductor　laser　diodes　of　95　mm　strip　width　and　4　mm　cavity　length　are　fabricated.　Without　any　active　cooling　process,　an　output　power　of　13.4　W　is　reached　at　15　A　injection　current　without　catastrophic　optical　mirror　damage　at　room　temperature.　By　introducing　the　asymmetric　LOC　waveguide,　the　far-field　test　shows　that　only　the　transverse　fundamental　mode　is　lased　with　a　vertical　far-field　angle　full　width　of　half　magnitude　of　22°.　©　2014　Chinese　Optics　Letters.