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arXiv · 2006.14531

On-demand generation of higher-order Fock states in quantum-dot--cavity systems

M. Cosacchi·J. Wiercinski·T. Seidelmann·M. Cygorek·A. Vagov·D. E. Reiter·V. M. Axt
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Abstract

The on-demand preparation of higher-order Fock states is of fundamental importance in quantum information sciences. We propose and compare different protocols to generate higher-order Fock states in solid state quantum-dot--cavity systems. The protocols make use of a series of laser pulses to excite the quantum dot exciton and off-resonant pulses to control the detuning between dot and cavity. Our theoretical studies include dot and cavity loss processes as well as the pure-dephasing type coupling to longitudinal acoustic phonons in a numerically complete fashion. By going beyond the two-level approximation for quantum dots, we study the impact of a finite exchange splitting, the impact of a higher energetic exciton state, and an excitation with linearly polarized laser pulses leading to detrimental occupations of the biexciton state. We predict that under realistic conditions, a protocol which keeps the cavity at resonance with the quantum dot until the desired target state is reached is able to deliver fidelities to the Fock state $| 5\rangle$ well above $40\,\%$.

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M. Cosacchi, J. Wiercinski, T. Seidelmann, M. Cygorek, A. Vagov, D. E. Reiter, V. M. Axt. 2020-06-25. On-demand generation of higher-order Fock states in quantum-dot--cavity systems. https://doi.org/10.1103/physrevresearch.2.033489

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