arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1608.05937cond-mat.str-elcond-mat.mes-hall
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自旋关联函数与准粒子衰变

Spin correlation functions and quasiparticle decay

Igor Poboiko, Mikhail Feigel'man

摘要:

研究了具有铁磁符号耦合和$z-z$交换常数$J_z = ΔJ$的一维各向异性XXZ自旋- $\frac12$模型,其中$Δ< 1$和$J$是XY自旋平面内的耦合.我们计算阻尼的低能量激发与$ω\ll T $由于其从热激发浴与温度$T \ll J$散射,考虑到非零曲率的激发光谱,$ε(q) = u q + δε(q)$。我们还计算了在$x \approx ut$处的纵向自旋-自旋关联函数$\langle S^z(x,t)S^z(0,0) \rangle$,并找到了扩散“波包“的形状。

英文摘要:

We study one-dimensional anisotropic XXZ spin-$\frac12$ model with ferromagnetic sign of the coupling and $z-z$ exchange constant $J_z = ΔJ$, where $Δ< 1$, and $J$ is the coupling within XY spin plane. We calculate damping of low-energy excitations with $ω\ll T $ due to their scattering from thermal excitation bath with temperature $T \ll J$, taking into account nonzero curvature of the excitation spectrum, $ε(q) = u q + δε(q)$. We calculate also longitudinal spin-spin correlation function $\langle S^z(x,t)S^z(0,0) \rangle$ at $x \approx ut$ and find the shape of the spreading "wave packet".

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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