The ground state energy at unitarity

Understand

We consider two-component fermions on the lattice in the unitarity limit.

• This is an idealized limit of attractive fermions where the range of the interaction is zero and the scattering length is infinite.
• Using Euclidean time projection, we compute the ground state energy using four computationally different but physically identical auxiliary-field methods.
• The best performance is obtained using a bounded continuous auxiliary field and a non-local updating algorithm called hybrid Monte Carlo.