Confinement-induced unatomic trimer states

TL;DR

This paper investigates how three identical atoms form unatomic trimer states during dimensional squeezing, revealing a continuous scale invariance and a critical dimension where the wave function behavior changes.

Contribution

It identifies the critical dimension for unatomic trimer formation and characterizes the wave function and contact evolution during the transition.

Findings

Unatomic regime occurs at dimension D̄=2.292 for three atoms.

Wave function exhibits power-law behavior below D̄.

Contacts evolve sharply at the crossover.

Abstract

The signature of an unatomic system is revealed by a continuous scale invariance that appears during a progressive dimensional squeezing of a resonantly interacting trimer. The unatomic regime is reached at the dimension $\overline D$, which for three identical atoms is found to be $\overline D=2.292$ - below this value, the trimer wave function at short distances displays a power-law behaviour. The fingerprint of this crossover is a sharp evolution of the contacts that characterizes the trimer momentum distribution tail.