Find a few good ones and examine them to see how they work, and adapt that technology to your own designs (don't just copy stuff, people don't like that, but learning from others' work is fine).
The super-hot ones aren't all that hot I'm afraid. These are not bad for early attempts, but your design is quite inefficient in places. Have a look at other lasers for inspiration - I have several, and there are literally thousands of others too.