Zero-magnon sound in quantum Heisenberg ferromagnets

Article

关键词: LONGITUDINAL DYNAMICAL SUSCEPTIBILITY;    RENORMALIZATION-GROUP APPROACH;    LOW-TEMPERATURE BEHAVIOR;    CORRELATION LENGTH;    SPIN FLUCTUATIONS;   

DOI  :  10.1103/PhysRevB.102.224437

来源: SCIE

【 摘 要 】

Using a functional renormalization-group approach, we show that at low temperatures and in a certain range of magnetic fields, the longitudinal dynamic structure factor of quantum Heisenberg ferromagnets in dimensions D <= 2 exhibits a well-defined quasiparticle peak with linear dispersion that we identify as zero-magnon sound. In D > 2, the larger phase space available for the decay into transverse spin waves leads only to a broad hump centered at zero frequency whose width scales linearly in momentum.

【 授权许可】

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