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Remotely pumped GHz antibunched emission from single exciton centers in GaAs

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 نشر من قبل Mingyun Yuan
 تاريخ النشر 2020
  مجال البحث فيزياء
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Quantum communication networks require on-chip transfer and manipulation of single particles as well as their interconversion to single photons for long-range information exchange. Flying excitons propelled by GHz surface acoustic waves (SAWs) are outstanding messengers to fulfill these requirements. Here, we demonstrate the acoustic manipulation of single exciton centers consisting of individual excitons bound to shallow impurities centers embedded in a semiconductor quantum well. Time-resolved photoluminescence studies show that the emission intensity and energy from these centers oscillate at the SAW frequency of 3.5 GHz. Furthermore, these centers can be remotely pumped via acoustic transport of flying excitons along a quantum well channel over several microns. Time correlation studies reveal that the centers emit anti-bunched light, thus acting as single-photon sources operating at GHz frequencies. Our results pave the way for the exciton-based on-demand manipulation and on-chip transfer of single excitons at microwave frequencies with a natural photonic interface.



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