The next generation of quantum computers will be scaled up from those which currently incorporate a few dozen qubits, to those of a few hundred with the development of noisy intermediate-scale quantum (NISQ) devices. This greatly increases the decoherence rate of any operation performed using NISQ hardware even under cryogenic conditions. Recently, much effort has been put into researching plasmonic-based devices that are able to perform ultrafast (picosecond) logic operations on a time scale that is faster than the decoherence rate of the system, while being able to operate nearer to room temperature. Plasmonic-based structures that use quantum dots as qubits are considered viable sources for room temperature quantum networks given their relatively low decoherence rate and their overall ease to fabricate compared to the often-used superconducting, i.e., SQUID-based devices. For quantum computing, one requires a reliable source of entangled particles which are compatible with repeaters and quantum error correction. Herein, we investigate the possibilities of time-dependent multipartite entanglement using a plasmonic-based archetype which couples quantum dots to a surface plasmon mode of a near-field transducer (NFT) and is fully integrated with a photonic waveguide. We demonstrate excellent fidelities of entanglement (>0.99) while varying the dipole moment and further investigate the effect of manipulating between the weak to strongly driven regimes. Altogether, we present a novel concept suitable for the implementation of dynamic quantum logic gates on an ultrafast scale closer to room temperature.
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