Geometry-induced entanglement in a mass-imbalanced few-fermion system

TL;DR

This paper demonstrates that few-fermion systems exhibit entanglement growth and divergence of quantum correlations during structural transitions driven by external potential shape changes, similar to many-body quantum phase transitions.

Contribution

It reveals that finite-size scaling can be applied to few-fermion systems to observe critical behavior near structural transitions, highlighting geometry-induced entanglement.

Findings

Divergences in von Neumann entropy at transition points

Power-law invariance of divergent quantities near transitions

Structural transitions driven by external potential shape changes

Abstract

Many-body systems undergoing quantum phase transitions reveal substantial growth of non-classical correlations between different parties of the system. This behavior is manifested by characteristic divergences of the von Neumann entropy. Here we show, that very similar features may be observed in one-dimensional systems of a few strongly interacting atoms when the structural transitions between different spatial orderings are driven by a varying shape of an external potential. When the appropriate adaptation of the finite-size scaling approach is performed in the vicinity of the transition point, few-fermion systems display a characteristic power-law invariance of divergent quantities.