标题： 海森堡自旋-1/2梯子的热导率：从可积性的弱破坏到强破坏 显示英文标题

标题： Heat conductivity of the Heisenberg spin-1/2 ladder: From weak to strong breaking of integrability

摘要： 我们研究了有限温度下Heisenberg自旋-1/2梯子的热导率$\kappa$，涵盖了整个范围的链间耦合$J_\perp$，通过使用多种数值方法和线性响应框架内的微扰理论。我们揭示出，基于简单黄金规则论证的微扰预测$\kappa \propto J_\perp^{-2}$，在严格极限$J_\perp \to 0$下有效，适用于非常广泛的$J_\perp$，在定性和定量上都成立。在大$J_\perp$极限下，我们展示了相反性质的幂律标度，即$\kappa \propto J_\perp^2$。 此外，我们展示了弱耦合和强耦合区域通过一个宽的最小值相连，该最小值略微低于各向同性点处的$J_\perp = J_\parallel$。 作为温度$T$的函数，这个最小值随着$\kappa \propto T^{-2}$下降到$T$，其数量级与交换耦合常数相当。 这些结果为$\kappa(J_\perp,T)$的自旋梯子提供了全面的图像。 显示英文摘要

摘要： We investigate the heat conductivity $\kappa$ of the Heisenberg spin-1/2 ladder at finite temperature covering the entire range of inter-chain coupling $J_\perp$, by using several numerical methods and perturbation theory within the framework of linear response. We unveil that a perturbative prediction $\kappa \propto J_\perp^{-2}$, based on simple golden-rule arguments and valid in the strict limit $J_\perp \to 0$, applies to a remarkably wide range of $J_\perp$, qualitatively and quantitatively. In the large $J_\perp$-limit, we show power-law scaling of opposite nature, namely, $\kappa \propto J_\perp^2$. Moreover, we demonstrate the weak and strong coupling regimes to be connected by a broad minimum, slightly below the isotropic point at $J_\perp = J_\parallel$. As a function of temperature $T$, this minimum scales as $\kappa \propto T^{-2}$ down to $T$ on the order of the exchange coupling constant. These results provide for a comprehensive picture of $\kappa(J_\perp,T)$ of spin ladders.