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

Ferromagnetic spin correlations in a few-fermion system

We study the spin correlations of a few fermions in a quasi-one-dimensional trap. Exact diagonalization calculations demonstrate that repulsive interactions between the two species drives ferromagnetic correlations. The ejection probability of an atom provides an experimental probe of the spin correlations. With more than five atoms trapped, the system approaches the itinerant Stoner limit. Los...

Deterministic preparation of a tunable few-fermion system.

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 inter...

On Fermion Entanglement

Under the historical definition of entanglement, namely that encountered in Einstein– Podolski–Rosen (EPR)–type experiments, it is shown that a particular Slater determinant is entangled. Thus a definition which holds that any Slater determinant is unentangled, found in the literature, is inconsistent with the historical definition. A generalization of the historical definition that embodies it...

Inhomogeneous state of few-fermion superfluids.

The few-fermion atomic gas is an ideal setting to explore inhomogeneous superfluid pairing analogous to the Larkin-Ovchinnikov state. Two up and one down-spin atom is the minimal configuration that displays an inhomogeneous pairing density, whereas imbalanced systems containing more fermions present a more complex pairing topology. With more than eight atoms trapped the system approaches the ma...

Quantum Entanglement and Geometry