Optical pumping of quantum dot micropillar lasers

Abstract

Arrays of quantum dot micropillar lasers are an attractive technology platform for various applications in the wider field of nanophotonics. Of particular interest is the potential efficiency enhancement as consequence of cavity quantum electrodynamics effects which makes them prime candidates for next generation photonic neurons in neural network hardware. However, in particular for optical pumping their power-conversion efficiency can be very low. Here we perform an in-depth experimental analysis of quantum dot microlasers and investigate their input-output relationship over a wide range of optical pumping conditions. We find that the current energy efficiency limitation is caused by disadvantageous optical pumping concepts and by a low exciton conversion efficiency. Our results indicate that for non-resonant pumping into the GaAs matrix (wetting layer), 3.4% (0.6%) of the optical pump is converted into lasing-relevant excitons, and of those only 2% (0.75%) provide gain to the lasing transition. Based on our findings we propose to improve the pumping efficiency by orders of magnitude by increasing the aluminium content of the AlGaAs/GaAs mirror pairs in the upper Bragg reflector.

References in corpus (7)

• Three dimensional waveguide-interconnects for scalable integration of photonic neural networks
• Bloch-wave engineering of quantum dot-micropillars for cavity quantum electrodynamics experiments
• Mutual coupling and synchronization of optically coupled quantum-dot micropillar lasers at ultra-low light levels
• Developing of a photonic hardware platform for brain-inspired computing based on $5\times 5$ VCSEL arrays
• Exploring the Photon-Number Distribution of Bimodal Microlasers
• Diffractive coupling for photonic networks: how big can we go?
• Strong light-matter coupling in the presence of lasing

Cited by in corpus (8)

• Spin-lasing in bimodal quantum dot micropillar cavities
• Low-threshold lasing of optically pumped micropillar lasers with Al${}_{0.2}$Ga${}_{0.8}$As/Al${}_{0.9}$Ga${}_{0.1}$As distributed Bragg reflectors
• Lagrangian descriptors for the Bunimovich stadium billiard
• Lasing of Quantum-Dot Micropillar Lasers under Elevated Temperatures
• Low-Threshold Surface-Emitting Whispering-Gallery Mode Microlasers
• Noise-induced dynamics and photon statistics in bimodal quantum-dot micropillar lasers
• Advanced micropillar cavities: room-temperature operation of microlasers
• Room-temperature, continuous wave lasing in planar microcavities with quantum dots