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arXiv · 2106.05351

Quantum Efficiency and Oscillator Strength of InGaAs Quantum Dots for Single-Photon Sources emitting in the Telecommunication O-Band

Jan Große·Pawel Mwrowinski·Nicole Srocka·Stephan Reitzenstein
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Abstract

We demonstrate experimental results based on time-resolved photoluminescence spectroscopy to determine the oscillator strength (OS) and the internal quantum efficiency (IQE) of InGaAs quantum dots (QDs). Using a strain-reducing layer (SRL) these QDs can be employed for the manufacturing of single-photon sources (SPS) emitting in the telecom O-Band. The OS and IQE are evaluated by determining the radiative and non-radiative decay rate under variation of the optical density of states at the position of the QD as proposed and applied in J. Johansen et al. Phys. Rev. B 77, 073303 (2008) for InGaAs QDs emitting at wavelengths below 1 $\mu$m. For this purpose, we perform measurements on a QD sample for different thicknesses of the capping layer realized by a controlled wet-chemical etching process. From numeric modelling the radiative and nonradiative decay rates dependence on the capping layer thickness, we determine an OS of 24.6 $\pm$ 3.2 and a high IQE of about (85 $\pm$ 10)% for the long-wavelength InGaAs QDs.

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Jan Große, Pawel Mwrowinski, Nicole Srocka, Stephan Reitzenstein. 2021-06-09. Quantum Efficiency and Oscillator Strength of InGaAs Quantum Dots for Single-Photon Sources emitting in the Telecommunication O-Band. https://doi.org/10.1063/5.0059458

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