High power diode laser for future applications

High power diode lasers went a long way from the 10 W or 20 W model of the early 90s to the 100 W, 150 W or even 200 W types of today. This was possible by improving both the efficiency of the semiconductor material by about 1/3 to 70% and the heat removal capability of the heat sinks used. We arrived at diode lasers which need 150 A or more and require a more and more refined cooling setup, especially if a rather stable wavelength is required. A further ramp-up of power would only benefit fewer and fewer applications as many of them need just 40 W or less from a diode laser.