Self-testing of different entanglement resources via fixed measurement settings

TL;DR

This paper demonstrates that a family of two-qubit entangled states can be self-tested using fixed measurement settings, simplifying resource requirements and enhancing practical feasibility in quantum information tasks.

Contribution

It introduces a method to self-test multiple entangled states with the same measurement settings using generalized tilted-CHSH operators, reducing measurement redundancy.

Findings

A family of two-qubit entangled states can be self-tested with fixed measurement settings.

The scheme is robust and feasible for practical experiments.

Results are applicable to various quantum information processing tasks.

Abstract

Self-testing, which refers to device independent characterization of the state and the measurement, enables the security of quantum information processing task certified independently of the operation performed inside the devices. Quantum states lie in the core of self-testing as key resources. However, for the different entangled states, usually different measurement settings should be taken in self-testing recipes. This may lead to the redundancy of measurement resources. In this work, we use fixed two-binary measurements and answer the question that what states can be self-tested with the same settings. By investigating the structure of generalized tilted-CHSH Bell operators with sum of squares decomposition method, we show that a family of two-qubit entangled states can be self-tested by the same measurement settings. The robustness analysis indicates that our scheme is feasible for practical experiment instrument. Moreover, our results can be applied to various quantum information processing tasks.