Magnetization and collective excitations of a magnetic dipole fermion gas

Mitsuru Tohyama

doi:10.7566/jpsj.82.124004

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arXiv · 1306.2078

Magnetization and collective excitations of a magnetic dipole fermion gas

Mitsuru Tohyama

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Abstract

The ground states and collective excitations of trapped Fermion gases consisting of atoms with magnetic dipole moment are studied using a time-dependent density-matrix approach. The advantages of the density-matrix approach are that one-body and two-body observables are directly calculated using one-body and two-body density matrices and that it has a clear relation to the Hartree-Fock (HF) and time-dependent HF theory. The HF calculations show the magnetization of the gases when the dipole-dipole interaction is strong. It is shown that the tensor properties of the dipole-dipole interaction are revealed in the excitation modes associated with spin degrees of freedom.

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Mitsuru Tohyama. 2013-06-10. Magnetization and collective excitations of a magnetic dipole fermion gas. https://doi.org/10.7566/jpsj.82.124004

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