# Maximum Spontaneous Magnetization and Nambu-Goldstone Mode

@article{Koma2017MaximumSM, title={Maximum Spontaneous Magnetization and Nambu-Goldstone Mode}, author={Tohru Koma}, journal={arXiv: Mathematical Physics}, year={2017} }

We study quantum antiferromagnetic Heisenberg models on a hypercubic lattice. We prove the following three theorems without any assumption: (i) The spontaneous magnetization which is obtained by applying the infinitesimally weak symmetry breaking field is equal to the maximum spontaneous magnetization at zero or non-zero low temperatures. (ii) When the spontaneous magnetization is non-vanishing at zero temperature, there appears a gapless excitation, Nambu-Goldstone mode, above an infinite…

## 4 Citations

Power-Law Decay Exponents of Nambu-Goldstone Transverse Correlations

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In the present chapter, which is the main chapter of part I, we develop rigorous and almost complete theories about LRO and SSB in the ground states of the antiferromagnetic Heisenberg model in…

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In a quantum many-body system where the Hamiltonian and the order operator do not commute, it often happens that the unique ground state of a finite system exhibits long-range order (LRO) but does…

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This document combines derivations and explanations of current proofs of an upper bound for the spin-wave spectrum of antiferromagnets in quantum Heisenberg moidel. The connection between…

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