High-efficiency multipartite entanglement purification of electron-spin states with charge detection

TL;DR

This paper introduces a highly efficient multipartite entanglement purification protocol for electron-spin states using charge detection, improving fidelity and resource utilization over existing methods.

Contribution

The authors develop a novel two-part MEPP that enhances efficiency by recycling subsystems and utilizing charge detection, surpassing previous protocols for electron-spin systems.

Findings

Achieves higher purification efficiency than existing MEPPs.

Utilizes charge detection to identify and recycle useful subsystems.

Enables direct high-fidelity N-electron ensemble preparation.

Abstract

We present a high-efficiency multipartite entanglement purification protocol (MEPP) for electron-spin systems in a Greenberger-Horne-Zeilinger state based on their spins and their charges. Our MEPP contains two parts. The first part is our normal MEPP with which the parties can obtain a high-fidelity N-electron ensemble directly, similar to the MEPP with controlled-not gates. The second one is our recycling MEPP with entanglement link from N'-electron subsystems (2 < N' < N). It is interesting to show that the N'-electron subsystems can be obtained efficiently by measuring the electrons with potential bit-flip errors from the instances which are useless and are just discarded in all existing conventional MEPPs. Combining these two parts, our MEPP has the advantage of the efficiency higher than other MEPPs largely for electron-spin systems.