Unity quantum efficiency in III-nitride quantum wells at low temperature: Experimental verification by time-resolved photoluminescence

ABSTRACTTaking advantages of short pulse excitation and time-resolved photoluminescence (PL), we have studied the exciton localization effect in a number of GaAsN alloys and GaAsN/GaAs quantum wells (QWs). In the PL spectra, an extra transition located at the higher energy side of the commonly reported N-related emissions is observed. By measuring PL dependence on temperature and excitation power along with PL dynamics study, the new PL peak has been identified as a transition of the band edge-related recombination in dilute GaAsN alloy and delocalized transition in QWs. Using selective excitation PL we further attribute the localized emission in QWs to the excitons localized at the GaAsN/GaAs interfaces. This interface-related exciton localization could be greatly reduced by a rapid thermal annealing.

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Time-Resolved Photoluminescence Study of 1.58 μm InGaAs/InGaAsP Quantum Wells

CLEO/Europe Conference on Lasers and Electro-Optics ◽

10.1109/cleoe.1998.719302 ◽

2005 ◽

Author(s):

C.H. Molloy ◽

D.J. Somerford ◽

P. Blood ◽

A.K. Wood

Keyword(s):

Quantum Wells ◽

Time Resolved ◽

Photoluminescence Study ◽

Time Resolved Photoluminescence

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Time-resolved photoluminescence studies of carrier diffusion in Si-doped GaInN/GaN quantum wells

2003 Conference on Lasers and Electro-Optics Europe (CLEO/Europe 2003) (IEEE Cat. No.03TH8666) ◽

10.1109/cleoe.2003.1312414 ◽

2005 ◽

Author(s):

S.M. Olaizola ◽

M.S. Skolnick ◽

D.J. Mowbray ◽

A.M. Fox ◽

P.J. Parbrook

Keyword(s):

Quantum Wells ◽

Time Resolved ◽

Carrier Diffusion ◽

Si Doped ◽

Photoluminescence Studies ◽

Time Resolved Photoluminescence

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Enhancement of quantum efficiency in InGaN quantum wells by using superlattice interlayers and pulsed growth

Lithuanian Journal of Physics ◽

10.3952/physics.v55i4.3221 ◽

2016 ◽

Vol 55 (4) ◽

Author(s):

Kazimieras Nomeika ◽

Mantas Dmukauskas ◽

Ramūnas Aleksiejūnas ◽

Patrik Ščajev ◽

Saulius Miasojedovas ◽

...

Keyword(s):

Quantum Wells ◽

Quantum Efficiency ◽

Light Emitting Diode ◽

Internal Quantum Efficiency ◽

Recombination Coefficient ◽

Time Resolved ◽

Mocvd Growth ◽

Lower Strain ◽

Type Contact ◽

Ingan Quantum Wells

Enhancement of internal quantum efficiency (IQE) in InGaN quantum wells by insertion of a superlattice interlayer and applying the pulsed growth regime is investigated by a set of time-resolved optical techniques. A threefold IQE increase was achieved in the structure with the superlattice. It was ascribed to the net effect of decreased internal electrical field due to lower strain and altered carrier localization conditions. Pulsed MOCVD growth also resulted in twice higher IQE, presumably due to better control of defects in the structure. An LED (light emitting diode) structure with a top p-type contact GaN layer was manufactured by using both growth techniques with the peak IQE equal to that in the underlying quantum well structure. The linear recombination coefficient was found to gradually increase with excitation due to carrier delocalization, and the latter dependence was successfully used to fit the IQE droop.

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Low-temperature internal quantum efficiency of GaInN/GaN quantum wells under steady-state conditions

Semiconductor Science and Technology ◽

10.1088/1361-6641/ac4b89 ◽

2022 ◽

Author(s):

Shawutijiang Sidikejiang ◽

Philipp Henning ◽

Philipp Horenburg ◽

Heiko Bremers ◽

Uwe Rossow ◽

...

Keyword(s):

Low Temperature ◽

Quantum Wells ◽

Internal Quantum Efficiency ◽

Structural Defects ◽

Measured Intensity ◽

Time Resolved ◽

Absorbed Power ◽

Radiative Losses ◽

Effects Of Temperature ◽

Excitation Conditions

Abstract We compare the low-temperature photoluminescence (PL) intensities of a range of GaInN/GaN quantum well (QW) structures under identical excitation conditions, mounting the samples side by side. Normalizing the measured intensity to the absorbed power density in the QWs, we find that low-temperature PL efficiencies of several samples, which show close to 100% IQE in time-resolved PL, saturate at nearly an identical value. Of course, this is strong indicative of being 100% IQE at low temperature for those efficient samples. Using the low-temperature PL efficiency as a ``Reference'', on the other hand, we observe not only the effects of temperature-independent non-radiative losses on the low-temperature IQE, but also are able to determine the IQE of arbitrary samples on an absolute scale. Furthermore, we prove the experimental results by comparing the low-temperature efficiencies of a sample with an initial 100% IQE after intentionally introducing structural defects with argon-implantation.

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