We explore the relationship between symmetrisation and entanglement through measurements on few-particle systems in a multi-well potential. In particular, considering two or three trapped atoms, we measure and distinguish correlations arising from two different physical origins: antisymmetrisation of the fermionic wavefunction and interaction between particles. We quantify this through the entanglement negativity of states, and the introduction of an antisymmetric negativity, which allows us to understand the role that symmetrisation plays in the measured entanglement properties. We apply this concept both to pure theoretical states and to experimentally reconstructed density matrices of two or three mobile particles in an array of optical tweezers.


J. H. Becher, E. Sindici, R. Klemt, S. Jochim, A. J. Daley, P. M. Preiss, “Measurement of  Identical Particle Entanglement and the Influence of Antisymmetrisation”, Phys. Rev. Lett. 125, 180402 (2020)


Related to Project C01, C02