Evidence for trap-assisted Auger recombination in MBE grown InGaN quantum wells by electron emission spectroscopy

Comment on "Direct Measurement of Auger Electrons Emitted from a Semiconductor Light-Emitting Diode under Electrical Injection: Identification of the Dominant Mechanism for Efficiency Droop" [Phys. Rev. Lett. 110, 177406 (2013)]

In a recent letter [Phys. Rev. Lett. 110, 177406 (2013)], presenting a spectroscopic study of the electrons emitted from the GaN p-cap of a forward-biased InGaN/GaN light-emitting diode (LED), the authors observed at least two distinct peaks in the electron energy distribution curves (EDCs), separated by about 1.5 eV, and concluded that the only viable explanation for the higher-energy peak was Auger recombination in the LED active region. We present full-band Monte Carlo simulations suggesting that the higher-energy peaks in the measured EDCs are probably uncorrelated with the carrier distrib…

Cathodoluminescence as an Effective Probe of Carrier Transport and Deep Level Defects in Droop-Mitigating InGaN/GaN Quantum Well Heterostructures

Commercial InGaN/GaN light emitting diode heterostructures continue to suffer from efficiency droop at high current densities. Droop mitigation strategies target Auger recombination and typically require structural and/or compositional changes within the multi-quantum well active region. However, these modifications are often accompanied by a corresponding degradation in material quality that decreases the expected gains in high-current external quantum efficiency. We study origins of these efficiency losses by correlating chip-level quantum efficiency measurements with structural and optical …

Explanation of low efficiency droop in semipolar $(20\bar 2\bar 1)$ InGaN/GaN LEDs through evaluation of carrier recombination coefficients

We report the carrier dynamics and recombination coefficients in single-quantum-well semipolar $(20\bar 2\bar 1)$ InGaN/GaN light-emitting diodes emitting at 440 nm with 93% peak internal quantum efficiency. The differential carrier lifetime is analyzed for various injection current densities from 5 $A/cm^2$ to 10 $kA/cm^2$, and the corresponding carrier densities are obtained. The coupling of internal quantum efficiency and differential carrier lifetime vs injected carrier density ($n$) enables the separation of the radiative and nonradiative recombination lifetimes and the extraction of the …

尺寸受限的室温单光子发射来自侧壁处理的分数维InGaN量子点：由态密度校正的超快载流子动力学和改进的信噪比决定

Size-Limited Room Temperature Single-Photon Emission from Sidewall-Treated Fractional Dimension InGaN Quantum Dots: Determined by Density-of-States-Corrected Ultrafast Carrier Dynamics and Improved Signal-to-Noise Ratio

研究通过化学和光电化学蚀刻制备的InGaN量子点实现了室温单光子发射，探讨了量子点尺寸对载流子动力学和信噪比的影响，揭示了量子点表面处理对单光子纯度的提升机制。

Spatial cross section of local and non-local upconversion processes for upconversion in InAs based quantum structures

Transients of upconverted photoluminescence (UPL) from molecular beam epitaxy (MBE) grown InAs quantum structures have been obtained. The results indicate the importance of spatial energy transfer cross section in the upconversion processes. The time constants determined suggest that several monolayer (ML) thick InAs quantum structures are the origin of upconversion. Both the time resolved and continuous wave data allow for the discussion of the dynamic balance between a local process (for example excitonic Auger process) and non-local process (for example two-step two-photon-absorption proces…