Sequential photon emissions from quad-excitons in single GaAs quantum dots

We observe single-photon interferograms for emission of a single self-assembled GaAs quantum dot. A phase stabilizer is applied to the interferometer, enabling us to trace autocorrelations of weak emissions with a photon-counting level. At low excitation, where the average number of excitons in a dot is less than one, interferography reveals a single exponential decay, reflecting excitonic decoherence. At moderately high excitation, polarization interference between the exciton-biexciton transitions is found to appear on the interferogram. The decoherence time and the binding energy of biexcitons are determined simultaneously.We observe single-photon interferograms for emission of a single self-assembled GaAs quantum dot. A phase stabilizer is applied to the interferometer, enabling us to trace autocorrelations of weak emissions with a photon-counting level. At low excitation, where the average number of excitons in a dot is less than one, interferography reveals a single exponential decay, reflecting excitonic decoherence. At moderately high excitation, polarization interference between the exciton-biexciton transitions is found to appear on the interferogram. The decoherence time and the binding energy of biexcitons are determined simultaneously.

Applied Physics LettersMar 20, 200627 citations

Simultaneous anti-bunched and super-bunched photons from a GaAs Quantum dot in a dielectric metasurface

Sanghyeok Park, Oleg Mitrofanov, Kusal M. Abeywickrama +9 more

Semiconductor quantum dots host a rich manifold of excitonic complexes, including neutral excitons that emit anti-bunched single photons and charged exciton complexes capable of producing super-bunched photons via cascade emission. Accessing both emission regimes from a single emitter would open routes to novel quantum protocols, including advanced quantum imaging. In practice, however, emission from charged exciton complexes is intrinsically weak, often orders of magnitude dimmer than neutral excitons, placing simultaneous dual-mode operation out of reach. Here, we overcome this limitation by embedding the quantum dot in a dielectric Mie-resonant metasurface that provides order-of-magnitude photoluminescence enhancement across both neutral and charged exciton transitions of a single GaAs quantum dot. Under identical non-resonant pumping conditions, the emission from the neutral exciton yields anti-bunched emission ( $g^{(2)}(0) < 0.5$ ) and the emission from positively charged exciton complexes shows super-bunched emission ( $g^{(2)}(0) > 3.5$ ) with comparable count rates (~12 kHz). Crucially, super-bunching emerges only when charged exciton emission spectrally overlaps with the Mie resonances and vanishes in un-patterned slabs, demonstrating that photonic engineering, is essential for accessing these weak quantum light states. These results demonstrate a scalable, position-tolerant platform for harnessing the full excitonic structure of solid-state emitters.Semiconductor quantum dots host a rich manifold of excitonic complexes, including neutral excitons that emit anti-bunched single photons and charged exciton complexes capable of producing super-bunched photons via cascade emission. Accessing both emission regimes from a single emitter would open routes to novel quantum protocols, including advanced quantum imaging. In practice, however, emission from charged exciton complexes is intrinsically weak, often orders of magnitude dimmer than neutral excitons, placing simultaneous dual-mode operation out of reach. Here, we overcome this limitation by embedding the quantum dot in a dielectric Mie-resonant metasurface that provides order-of-magnitude photoluminescence enhancement across both neutral and charged exciton transitions of a single GaAs quantum dot. Under identical non-resonant pumping conditions, the emission from the neutral exciton yields anti-bunched emission ($g^{(2)}(0) < 0.5$) and the emission from positively charged exciton complexes shows super-bunched emission ($g^{(2)}(0) > 3.5$) with comparable count rates (~12 kHz). Crucially, super-bunching emerges only when charged exciton emission spectrally overlaps with the Mie resonances and vanishes in un-patterned slabs, demonstrating that photonic engineering, is essential for accessing these weak quantum light states. These results demonstrate a scalable, position-tolerant platform for harnessing the full excitonic structure of solid-state emitters.

cond-mat.mes-hallCross-listedarXiv:2603.03186Mar 4, 2026

Photon Correlation in GaAs Self-assembled Quantum Dots

小口信行, 木戸義勇, 迫田和彰 +11 more

Applied Physics ExpressApr 1, 20080 citations

Single photon emission from individual GaAs quantum dots

J. Hours, Spyridon Varoutsis, Mathieu Gallart +6 more

We report on photon correlation measurements on a single quantum dot formed at fluctuations of the interface of a GaAs/GaAlAs quantum well. We demonstrate that under pulsed nonresonant excitation, the quantum dot emits a single photon per pulse. This shows that after the photon emission, there is no refill of the quantum dot by the nearby two-dimensional reservoir of delocalized states. The possibility of delivering Fourier transform limited single photons makes this system a good candidate for exciton- and photon-based quantum information processing schemes.We report on photon correlation measurements on a single quantum dot formed at fluctuations of the interface of a GaAs/GaAlAs quantum well. We demonstrate that under pulsed nonresonant excitation, the quantum dot emits a single photon per pulse. This shows that after the photon emission, there is no refill of the quantum dot by the nearby two-dimensional reservoir of delocalized states. The possibility of delivering Fourier transform limited single photons makes this system a good candidate for exciton- and photon-based quantum information processing schemes.

Applied Physics LettersApr 3, 200366 citations

Photon-emission properties of quantum-dot-based single-photon sources under different excitations

Y. Ben, Zhibiao Hao, Changzheng Sun +2 more

Applied Physics BJun 9, 20052 citations

g^{(2)}(0) < 0.5

) and the emission from positively charged exciton complexes shows super-bunched emission (

g^{(2)}(0) > 3.5

) with comparable count rates (~12 kHz). Crucially, super-bunching emerges only when charged exciton emission spectrally overlaps with the Mie resonances and vanishes in un-patterned slabs, demonstrating that photonic engineering, is essential for accessing these weak quantum light states. These results demonstrate a scalable, position-tolerant platform for harnessing the full excitonic structure of solid-state emitters.