Exploring qubit-qubit entanglement mediated by one-dimensional plasmonic nanowaveguides

TL;DR

This paper investigates how plasmonic nanowaveguides can mediate entanglement between two qubits, revealing phenomena like spontaneous entanglement formation, sudden birth, revival, and steady-state entanglement influenced by inter-qubit distance.

Contribution

It demonstrates the control of qubit-qubit entanglement via plasmonic modes in a one-dimensional nanowaveguide, including steady-state entanglement characterization.

Findings

Observation of spontaneous entanglement formation

Identification of entanglement sudden birth and revival

Steady-state entanglement depending on inter-qubit distance

Abstract

We exploit the qubit-qubit coupling induced by plasmon-polariton modes in a one-dimensional nanowaveguide to obtain various two-qubit entanglement situations. Firstly, we observe three phenomena occurring when preparing the initial state of the system and leaving it freely relax: spontaneous formation of entanglement, sudden birth and revival. Then, we show that plugging a laser to each of the qubit, the system arrives to an steady state which, depending on their inter-qubit distance, can also be entangled. For this situation, we also characterize the quantum state of the system showing the entanglement-purity- diagram typical for two-qubit systems.