Contact interaction in an unitary ultracold Fermi gas

Abstract

An ultracold Fermi atomic gas at unitarity presents universal properties that in the diluted limit can be well described by a contact interaction. By employing a guide function with correct boundary conditions and making simple modifications to the sampling procedure we are able to handle for the first time a true contact interaction in a quantum Monte Carlo calculation. The results are obtained with small variances. Our calculations for the Bertsch and contact parameters are in excellent agreement with published experiments. The possibility of using a more faithfully description of ultracold atomic gases can help uncover features yet unknown of the ultracold atomic gases. In addition, this work paves the way to perform quantum Monte Carlo calculations for systems interacting with contact interactions, where in many cases the description using potentials with finite effective range might not be accurate.

References in corpus (17)

• Theory of ultracold Fermi gases
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• Monte Carlo calculations for Fermi gases in the unitary limit with a zero-range interaction
• High-fidelity pseudopotentials for the contact interaction

Cited by in corpus (10)

• The Bose polaron problem: effect of mass imbalance on binding energy
• Quantum Monte-Carlo study of the Bose polaron problem in a one-dimensional gas with contact interactions
• Quantum behavior of a heavy impurity strongly coupled to a Bose gas
• Path integral Monte Carlo ground state approach: Formalism, implementation, and applications
• Effective-range dependence of resonant Fermi gases
• Finite-range effects in the unitary Fermi polaron
• Spatial structure of the pair wavefunction and the density correlation functions at the BEC-BCS crossover
• Pair Approximating the Action For Molecular Rotations in Path Integral Monte Carlo
• Properties of fermionic systems with the Path-integral ground state method
• Cold atoms beyond atomic physics