On-demand sources of non-classical light play an important role in quantum information and metrology [Ref. 1], and semiconductor quantum dot (QD) sources promise high-quality and efficient single and entangled photons [Refs. 1, 2]. At the same time, other states of light have been observed in the QD emission [Refs. 3, 4, 5, 6] as the nature of the emitted light relates with the dynamics of the electronic state of the QD. In particular, when the dot is excited by a pulse of light, charge and/or exciton capture processes within the same pulse cycle can cause multi-photon emission.
Here, we predict and measure – using a photon-number-resolving superconducting-nanowire single photon detector – photon correlations and photon number statistics in light emitted by a QD embedded in a semiconductor nanowire [Ref. 2] excited with non-resonant pulses of different lengths.
We model the excitation and emission process as a Markov chain. This allows one to keep track of the photon number distributions of the involved transitions – such as: exciton (X), bi-exciton (XX) and charged exciton (X- ) – along with their coincidences. An illustration of a model and its estimates are presented in Figure 1. We study the role of different parameters in the model, such as pulse lengths and intensities, to explain the observed experimental results.
[ 1 ] R. Trivedi et al. Generation of Non-Classical Light Using Semiconductor Quantum Dots, Adv. Quantum Technol. 2020, 3, 1900007
[ 2 ] M. Reimer, G. Bulgarini, N. Akopian et al. Bright single-photon sources in bottom-up tailored nanowires, Nat Commun. 3, 737 (2012)
[ 3 ] K. Fisher et al. Signatures of two-photon pulses from a quantum two-level system, Nature Physics volume 13, 649–654 (2017)
[ 4 ] E. B. Flagg, et al. Dynamics of Nonclassical Light from a Single Solid-State Quantum Emitter, Phys. Rev. Letters 109, 163601 (2012)
[ 5 ] M. H. Baier et al. Quantum-dot exciton dynamics probed by photon-correlation spectroscopy, Phys. Rev. B. 73, 205321 (2006)
[ 6 ] G. Sallen et al. Exciton dynamics of a single quantum dot embedded in a nanowire, Phys. Rev. B. 80, 085310, (2009)
|Presenter name||Sai Sreesh|
|How will you attend ICAP-27?||I am planning on in-person attendance|