Transient thermal tuning properties of single emitters in actively cooled high-power cm-bar arrays

摘要

Transient thermal properties of actively cooled InAlGaAs-based high-power diode laser arrays, so-called 'cm-bars', are investigated for 'low-frequency' pulsed operation with a repetition rate of 0.1-10 Hz. Under these operation conditions the devices experience almost complete thermal cycles between the temperature of the heat sink and the operation temperature typical for continuous wave operation. We analyze the thermal tuning behavior that is governed by the thermal bandgap shift (85%) but substantially modified by pure pressure tuning (15%). During operation further modification arises from inhomogeneous temperature distribution along the 'cm-bar'. Our results offer the possibility specifying optimum operation condition of 'low-frequency' pulsed operation resulting in improved reliability.