I bought some laser diodes on amazon. They're the typical small red 5mW lasers. Just wanted to see if the diode handle more power so i put about 20 - 30mW through it. Nice bright red dot on the wall, but then it dims and dims. The diode didn't get super hot it just got a little hot. But I've never seen such a dramatic change in resistance with so little thermal energy. Would someone mind explaining why? I know the basics behind a diode, I don't know much about the physics behind lasers though, but since it is called a laser "diode," if i treat it as a diode, which is a semiconductor, wouldn't thermal energy just put more charge carriers in the conduction band?