Chirality-assisted enhancement of tripartite entanglement in waveguide QED

TL;DR

This paper investigates how chiral waveguides can enhance and sustain tripartite entanglement among quantum emitters, with potential applications in quantum networking and communication.

Contribution

It demonstrates that chiral waveguides with asymmetric decay rates can significantly boost and prolong tripartite entanglement compared to symmetric setups.

Findings

Tripartite entanglement can be increased by 35% with asymmetric decay rates.

Chirality extends the lifetime of entanglement.

Detunings and spontaneous emission influence entanglement robustness.

Abstract

We study the generation and control of genuine tripartite entanglement among quantum emitters (QEs) that are side coupled to one-dimensional spin-momentum locked (or chiral) waveguides. By applying the machinery of Fock state master equations along with the recently proposed concurrence fill measure of tripartite entanglement [S. Xie and J. H. Eberly, Phys. Rev. Lett. 127, 040403 (2021)], we analyze how three-photon Gaussian wavepackets can distribute entanglement among two and three QEs. We show that with a five times larger waveguide decay rate in the right direction as compared to the left direction, the maximum value of tripartite entanglement can be elevated by 35% as compared to the symmetric scenario where both left and right direction decay rates are equal. Additionally, chirality can maintain the tripartite entanglement for longer times in comparison to the corresponding symmetric decay rate situation. Finally, we study the influence of detunings and spontaneous emission on the resulting entanglement. We envision quantum networking and long-distance quantum communication as two main areas of applications of this work.