Deterministic Preparation of a Tunable Few-Fermion System

TLDR

Few‑fermion systems form the fundamental building blocks of matter, exemplified by atoms and nuclei. The study aims to enable quantum simulation of strongly correlated few‑body systems. The authors realized a fully controllable few‑body quantum system using ultracold fermionic atoms trapped in an optical dipole trap. They prepared ground‑state few‑fermion systems of 1–10 particles with ~90% fidelity and demonstrated tunable interparticle interactions via a Feshbach resonance, observing interaction‑induced energy shifts in a repulsive atom pair.

Abstract

Systems consisting of few interacting fermions are the building blocks of matter, with atoms and nuclei being the most prominent examples. We have created a few-body quantum system with complete control over its quantum state using ultracold fermionic atoms in an optical dipole trap. Ground-state systems consisting of 1 to 10 particles are prepared with fidelities of ∼90%. We can tune the interparticle interactions to arbitrary values using a Feshbach resonance and have observed the interaction-induced energy shift for a pair of repulsively interacting atoms. This work is expected to enable quantum simulation of strongly correlated few-body systems.