Can I Use Code 100 Turnouts with Code 83 Track On HO Scale

Not a problem. Atlas makes code 100 to code 83 transition joiners The rail joiners look like standard joiners except that they have a step in the middle. See my third post for info on Walthers transition track.
 
Correction to my first post. The transition track sections that I mentioned are not an Atlas product but Walthers. The part number is 948-897. Made by Shinohara. Brain fog problem brought on by my old age. Sorry.
 
You can adapt a regular rail joiner so that it will take both Code 83 and Code 100. I used Code 100 insulfrogs with Atlas Code 83 rail and it worked quite well. You can see this mod under a previous thread "Which switch to buy". It was a simple matter of pushing down on the Code 100 (insert a spacer underneath the Code 83 track) until the top of the Code 100 was flush with the top of the Code 83. A bit of solder kept the two pieces in place.

Bob M.