Time‐resolved reconstruction of defect creation sequences in diode lasers

Hempel, Martin; Tomm, Jens W.; Hortelano, V.; Michel, N.; Jim, Jeffrey; Krakowski, M.; Elsaesser, Thomas

doi:10.1002/lpor.201200039

Cited by 22 publications

(31 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Usually, this temperature is measured at the laser front facet; albeit, it has also been measured inside the cavity for lasers showing internal COD [2]. These critical temperatures are surprisingly low, and the understanding about their physical meaning is ambiguous.…”

Section: Introductionmentioning

confidence: 99%

“…The local temperature has been routinely characterized by measuring temperature profiles of the operating devices using a variety of techniques, such as Raman microscopy (µR) [1,2,4], thermal infrared imaging (TII) [2], thermoreflectance (TR) [1][2][3][4], and micro-Photoluminiscence (µPL). The outcome of all these studies is limited by the size of the sampled area, with a lateral resolution slightly submicrometric for the techniques using a focused laser beam, i.e.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

About the physical meaning of the critical temperature for catastrophic optical damage in high power quantum well laser diodes

2016

View full text Add to dashboard Cite

Short title: About the physical meaning of the critical temperature for catastrophic optical damage AbstractIt is usually assumed that the catastrophic optical damage of high power laser diodes is launched when a critical local temperature (Tc) is reached; temperatures ranging from 120ºC to 200ºC were experimentally reported. However, the physical meaning of Tc in the degradation process is still unclear. In this work we show that, in the presence of a local heat source in the active region, the temperature of the laser structure, calculated using finite element methods, is very inhomogeneously distributed among the different layers forming the device. This is due to the impact that the low dimensionality and the thermal boundary resistances have on the thermal transport across the laser structure. When these key factors are explicitly considered, the quantum well (QW) temperature can be several hundred degrees higher than the temperature of the guides and cladding layers. Due to the size of the experimental probes, the measured critical temperature is a weighted average over the QW, guides and claddings. We show the existence of a great difference between the calculated average temperature, equivalent to the experimentally measured temperature, and the peak temperature localized in the QW. A parallel study on double heterostructure lasers is also included for comparison.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

About the physical meaning of the critical temperature for catastrophic optical damage in high power quantum well laser diodes

2016

View full text Add to dashboard Cite

show abstract

“…Generally, these DLDs are guided along the laser cavity by the optical field, instead of being aligned along a crystal axis. This is better seen in broad emitter lasers, where one can appreciate DLDs deviating from the cavity axis, being guided by ring modes [4]. Another interesting feature of the DLDs revealed by CL in these lasers is that they seem to propagate in a discontinuous sequence.…”

Section: Contents Lists Available At Sciencedirectmentioning

confidence: 93%

“…The degradation mode is achieved by the destruction of the active region of the laser following a thermal runaway process. In order to raise a scenario of the sudden degradation one needs to identify the defects produced during the degradation, and then to establish the physical mechanisms responsible for the formation of those defects, and their subsequent propagation forming the characteristic dark line defects (DLDs) associated with the catastrophic degradation [4,9].…”

Section: Defects In the Laser Structurementioning

confidence: 99%

“…Electron beam excited techniques, e.g. cathodoluminescence (CL), and electron beam induced current (EBIC), are powerful tools suitable to observe the main defects generated during the degradation process [4,5]. This is a "post mortem" analysis; however, it permits to establish degradation hypotheses, which would allow to set up a physical model providing the main steps leading to the laser degradation [6].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Catastrophic optical damage of high power InGaAs/AlGaAs laser diodes

Souto¹,

Pura²,

Torres³

et al. 2016

Microelectronics Reliability

View full text Add to dashboard Cite

The defects generated by the catastrophic optical degradation (COD) of high power laser diodes have been examined using cathodoluminescence (CL). Discontinuous dark lines that correspond to different levels of damage have been observed along the ridge. Finite element methods have been applied to solve a physical model for the degradation of the diodes that explicitly considers the thermal and mechanical properties of the laser structure. According to this model, the COD is triggered by a local temperature enhancement that gives rise to thermal stresses leading to the generation of dislocations. Damage is initially localized in the QW, and when it propagates to the waveguide layers the laser ends its life.

show abstract

Short-wavelength infrared defect emission as a probe of degradation processes in 980 nm single-mode diode lasers

Hempel

Tomm

Yue

et al. 2014

Laser & Photonics Reviews

View full text Add to dashboard Cite

Infrared emission from 980-nm single-mode high power diode lasers is recorded and analyzed in the wavelength range from 0.8 to 8.0 μm. A pronounced short-wavelength infrared (SWIR) emission band with a maximum at 1.3 μm originates from defect states located in the waveguide of the devices. The SWIR intensity is a measure of the nonequilibrium carrier concentration in the waveguide, allowing for a non-destructive waveguide mapping in spatially resolved detection schemes. The potential of this approach is demonstrated by measuring spatially resolved profiles of SWIR emission and correlating them with mid-wavelength infrared (MWIR) thermal emission along the cavity of devices undergoing repeated catastrophic optical damage. The enhancement of SWIR emission in the damaged parts of the cavity is due to a locally enhanced carrier density in the waveguide and allows for an analysis of the spatial damage patterns. The figure shows a side view of a diode laser during catastrophic degradation as recorded by a thermocamera within 5 successive current pulses. The geometry of the device is given in grayscale. The position of the laser chip is indicated by the

show abstract

Time‐resolved reconstruction of defect creation sequences in diode lasers

Cited by 22 publications

References 18 publications

About the physical meaning of the critical temperature for catastrophic optical damage in high power quantum well laser diodes

About the physical meaning of the critical temperature for catastrophic optical damage in high power quantum well laser diodes

Catastrophic optical damage of high power InGaAs/AlGaAs laser diodes

Short-wavelength infrared defect emission as a probe of degradation processes in 980 nm single-mode diode lasers

Contact Info

Product

Resources

About