Practical and efficient experimental characterization of multiqubit stabilizer states

TL;DR

This paper introduces a scalable, linear-in-qubits method for efficiently characterizing multiqubit stabilizer states, providing comprehensive information on fidelity, entanglement, and nonlocality, demonstrated through photonic experiments.

Contribution

It presents a novel, efficient characterization technique for stabilizer states that scales linearly with qubits and simultaneously assesses multiple quantum properties.

Findings

Successful experimental characterization of four-qubit cluster state

Efficient assessment of GHZ states with three and four qubits

Method extends to larger quantum information tasks

Abstract

Vast developments in quantum technology have enabled the preparation of quantum states with more than a dozen entangled qubits. The full characterization of such systems demands distinct constructions depending on their specific type and the purpose of their use. Here we present a method that scales linearly with the number of qubits for characterizing stabilizer states. Our approach allows simultaneous extraction of information about the fidelity, the entanglement, and the nonlocality of the state and thus is of high practical relevance. We demonstrate the efficient applicability of our method by performing an experimental characterization of a photonic four-qubit cluster state and three- and four-qubit Greenberger-Horne-Zeilinger states. Our scheme can be directly extended to larger-scale quantum information tasks.