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We present a general formalism for deriving the thermodynamics of ferromagnets consisting of "atoms" carrying an arbitrary irreducible representation of and coupled through long-range two-body quadratic interactions. Using this formalism, we derive the thermodynamics and phase structure of ferromagnets with atoms in the doubly symmetric or doubly antisymmetric irreducible representations. The symmetric representation leads to a paramagnetic and a ferromagnetic phase with transitions similar to the ones for the fundamental representation studied before. The antisymmetric representation presents qualitatively new features, leading to a paramagnetic and two distinct ferromagnetic phases that can coexist over a range of temperatures, two of them becoming metastable. Our results are relevant to magnetic systems of atoms with reduced symmetry in their interactions compared to the fundamental case.
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This content will become publicly available on September 1, 2026
Nonabelian ferromagnets with three-body interactions
We derive the phase structure and thermodynamics of ferromagnets consisting of elementary magnets carrying the adjoint representation of SU(N) and coupled through two-body quadratic interactions. Such systems have a continuous SU(N) symmetry as well as a discrete conjugation symmetry. We uncover a rich spectrum of phases and transitions, involving a paramagnetic and two distinct ferromagnetic phases that can coexist as stable and metastable states in different combinations over a range of temperatures. The ferromagnetic phases break SU(N) invariance in various channels, leading to spontaneous magnetization. Interestingly, the conjugation symmetry also breaks over a range of temperatures and group ranks N, providing a realization of a spontaneously broken discrete symmetry.
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- PAR ID:
- 10651324
- Publisher / Repository:
- Nuclear Physics B
- Date Published:
- Journal Name:
- Nuclear Physics B
- Volume:
- 1018
- Issue:
- C
- ISSN:
- 0550-3213
- Page Range / eLocation ID:
- 117094
- Subject(s) / Keyword(s):
- ferromagnetism, SU(N), adjoint, phase transitions, symetry breaking, discrete symmetries,l discrete symmetry breaking, metastability
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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