Catastrophic optical damage at front and rear facets of diode lasers

Abstract

Single-pulse tests of the catastrophic optical damage (COD) are performed for three batches of diode lasers with different gain-regions. The tests involve in situ inspection of front, rear, and side of the devices by a thermocamera. Devices with an Al-containing gain-region show COD at the front facet, as expected for strong facet heating via surface recombination and reabsorption of laser light. In contrast, Al-free devices with low surface recombination rates tend to fail at the rear facet, pointing to a different heating scenario. The high carrier density at the rear facet favors heating and COD via Auger recombination processes.

Mechanisms and fast kinetics of the catastrophic optical damage (COD) in GaAs‐based diode lasers

“…Reports on lowered COD thresholds in aged diode lasers [20][21][22][23] indicate the existence of this type of feedback loop. The re-ignition of the thermal runaway by subsequent current pulses [24,25] represents an indirect evidence for this behavior. COD schemes similar to Fig.…”

“…2). Only recently Hempel et al [24,25] have given direct evidence for multiple ignitions by monitoring the presence of the runaway process during subsequent pulses by thermography.…”

Near-field dynamics of broad area diode laser at very high pump levels

“…At the end we have the same resulting damage as in the case of a ∼500 ns long pulse (2 pulses each 300 ns minus 100 ns to restore the thermal situation after the initial COD pulse). This justifies the idea to decelerate the COD process 7,8,15 by time-slicing a single current pulse into a sequence of short pulses. We now consider the energy balance of the COD process.…”

“…Details of this approach have been described elsewhere. 7,8 Figures 1(a)-1(d), show the NF dynamics from one of the investigated devices at 8.5 A, i.e., at ∼40 times threshold current. Figure 1(a) covers the entire duration of the current pulse of 300 ns (temporal resolution ∼675 ps).…”

Design and Simulation of an 808 nm InAlAs/AlGaAs GRIN-SCH Quantum Dot Laser Diode

“…The actual limiting event can take one of a number of forms such as catastrophic optical damage [3][4][5] or spatial hole burning [6][7][8]. The general approach to raising these limits is to design a heterostructure which effectively confines high power in the lasing mode while maintaining low internal optical intensities.…”