Use oscillating GOL. (Life sub-type.) Preferably encase it so it can still move around in its wobbling position in diamond, the diamond helping to shield it from damaging stray photons, electrons, and maybe even neutrons, depending on the laser, and to give the GOL heat bi-product a greater surface area to touch the passing photons. I use GOL for heating, and star for cooling. Just drag some GOL around on your screen until you get a small oscillating 3*3 square of it, make sure it is in a steady form though. Just copy and paste and wallah.
My best experiences have been with lightning, But it isn't persistent as GOL. So lightning STARTS out as high temp, and GOL STAYS at a low temp. Thats only my experiences though...
PS:
This is my first post and first time on the site in MONTHS