Spectral intensity distribution of trapped fermions

Abstract

To calculate static response properties of a many body system, local density approximation (LDA) can be safely applied. But applicability of LDA is limited for the case of dynamical response functions since dynamics of the system needs to be considered as well. To examine this in the context of cold atoms, we consider a system of non-interacting spin-$1/2$ fermions confined by a harmonic trapping potential. We have calculated a very important response function, the spectral intensity distribution function (SIDF), both exactly and using LDA at zero temperature and compared with each other for different dimensions, trap frequencies and momenta. The behavior of the SIDF at a particular momentum can be explained by noting the behavior of the density of states (DOS) of the free system (without trap) in that particular dimension. The agreement between exact and LDA SIDFs becomes better with increase in dimensions and number of particles.

10 pages, 4 figures

References in corpus (11)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Spin-Orbit Coupled Degenerate Fermi Gases
• Spin-Injection Spectroscopy of a Spin-Orbit Coupled Fermi Gas
• Using photoemission spectroscopy to probe a strongly interacting Fermi gas
• A Bose-Einstein Condensate in a Uniform Light-induced Vector Potential
• Observation of pseudogap behavior in a strongly interacting Fermi gas
• Radiofrequency spectroscopy of a strongly interacting two-dimensional Fermi gas
• BCS-BEC crossover induced by a synthetic non-Abelian gauge field
• Measuring the one-particle excitations of ultracold fermionic atoms by stimulated Raman spectroscopy
• Trapped fermions in a synthetic non-Abelian gauge field
• Pairing and radio-frequency spectroscopy in two-dimensional Fermi gases