Polarization of interacting bosons with spin

Eli Eisenberg; Elliott H. Lieb

doi:10.1103/physrevlett.89.220403

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Polarization of interacting bosons with spin

Eli Eisenberg·Elliott H. Lieb

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Abstract

We demonstrate rigorously that in the absence of explicit spin-dependent forces one of the ground states of interacting bosons with spin is always fully polarized -- however complicated the many-body interaction potential might be. Depending on the particle spin, the polarized ground state will generally be degenerate with other states, but one can specify the exact degeneracy. For T>0 the magnetization and susceptibility necessarily exceed that of a pure paramagnet. These results are relevant to recent experiments exploring the relation between triplet superconductivity and ferromagnetism, and the Bose-Einstein condensation of atoms with spin. They eliminate the possibility, raised in some theoretical speculations, that the ground state or positive temperature state might be antiferromagnetic.

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BibTeX RIS

Eli Eisenberg, Elliott H. Lieb. 2002-10-31. Polarization of interacting bosons with spin. https://doi.org/10.1103/physrevlett.89.220403

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