np spin correlations in the deuteron ground state

TL;DR

This paper investigates the quantum entanglement of proton and neutron spins in the deuteron, revealing maximal entanglement at zero total angular momentum projection and persistent entanglement in superpositions.

Contribution

It provides new insights into spin entanglement in the simplest nucleus, analyzing different angular momentum states and their entanglement properties.

Findings

Maximum entanglement occurs at zero total angular momentum projection

Strong entanglement persists in superposition states

Spin entanglement is fundamental in the deuteron structure

Abstract

The deuteron is the simplest atomic nucleus made of two particles - a proton and a neutron. In this work, we study how their spins are quantum entangled with each other. We study two cases: when the deuteron is in a fixed projection of total angular momentum, and when it exists in a superposition of all projections. Our findings show that the spins are most entangled when the total projection is zero, and that strong entanglement still exists even when all spin states are superposed.