Quantification of quantumness in neutrino oscillations

Fei Ming,Jiajie Ling,Dong Wang,Xue-Ke Song,Liu Ye

doi:10.1140/epjc/s10052-020-7840-y

Abstract

Neutrino oscillation is an important physical phenomenon in elementary particle physics, and its nonclassical features can be revealed by the Leggett–Garg inequality. It shows that its quantum coherence can be sustained over astrophysical length scales. In this work, we investigate the measure of quantumness in experimentally observed neutrino oscillations via the nonlocal advantage of quantum coherence (NAQC), quantum steering, and Bell nonlocality. From various neutrino sources, ensembles of reactor and accelerator neutrinos are analyzed at distinct energies, such as Daya Bay (0.5 km and 1.6 km) and MINOS (735 km) collaborations. The NAQC of two-flavor neutrino oscillation is characterized experimentally compared to the theoretical prediction. It exhibits non-monotonously evolutive phenomenon with the increase of energy. Furthermore, it is found that the NAQC is a stronger quantum correlation than quantum steering and Bell nonlocality even in the order of km. Hence, for an arbitrary bipartite neutrino-flavor state with achieving a NAQC, it must be also a steerable and Bell nonlocal state. The results might offer an insight into the neutrino oscillation for the further applications on quantum information processing.

Highlights

Dating from over half a century ago, the interesting phenomenon of the neutrino oscillation (NO) was discovered [1,2,3,4,5]
The nonlocal advantage of quantum coherence (NAQC) can vanish in some time periods, while Bell nonlocality and quantum steering not
Compared with electron NOs, we conclude that the NAQC is a stronger quantum correlation than Bell nonlocality and quantum steering with regard to muon NOs

Summary

Introduction

Dating from over half a century ago, the interesting phenomenon of the neutrino oscillation (NO) was discovered [1,2,3,4,5]. They can be reduced to the effective two-flavor ones [26] They can be investigated via considering them as the two-mode systems, to that the two-qubit quantum systems. Some works [27,28,29,30] have tested the quantumness of NOs by utilizing the Leggett–Garg inequality (LGI) treated as the temporal Bell inequality It suggests that the classical limits can be violated with the LGI in experimentally observed NOs [31]. We focus on exploring the NAQC, quantum steering, and Bell nonlocality in experimentally observed NOs. It is found that the NAQC for neutrino-flavor states can be captured based on the l1 norm of coherence. 3, we capture the NAQC, quantum steering, and Bell nonlocality in experimentally observed NOs. In Sect.

Two-flavor NOs

Findings

Conclusions