The nature of the normal state of cuprate superconductors continues to stimulate considerable speculation. Of particular interest has been the linear temperature dependence of the in-plane resistivity in the low-temperature limit, which violates the prediction for a Fermi liquid. We present measurements of anisotropic resistivity in ${\mathrm{La}}_{2-x}{\mathrm{Sr}}_x{\mathrm{CuO}}_4$ that confirm the strange-metal behavior for crystals with doped-hole concentration $p=x>p^{*}\sim 0.19$ and contrast with the nonmetallic behavior for $p<p^{*}$. We propose that the changes at $p^{*}$ are associated with a first-order transition from doped Mott insulator to conventional metal; the transition appears as a crossover due to intrinsic dopant disorder. We consider results from the literature that support this picture; in particular, we present a simulation of the impact of the disorder on the first-order transition and the doping dependence of stripe correlations. Below $p^{*}$, the strong electronic interactions result in charge and spin stripe correlations that percolate across the ${\mathrm{CuO}}_2$ planes; above $p^{*}$, residual stripe correlations are restricted to isolated puddles. We suggest that the $T$-linear resistivity results from scattering of quasiparticles from antiferromagnetic spin fluctuations within the correlated puddles. This is a modest effect compared to the case at $p<p^{*}$, where the data suggest that there are no coherent quasiparticles in the normal state.

中文翻译：

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La2−xSrxCuO4 中条带渗流转变中从非金属到奇异金属

铜酸盐超导体正常状态的性质继续激发人们的大量猜测。特别令人感兴趣的是低温极限下面内电阻率的线性温度依赖性，这违反了费米液体的预测。我们提出了各向异性电阻率的测量${拉}_{2-X}{锶}_X{\mathrm{氧化铜}}_4$证实了具有掺杂空穴浓度的晶体的奇异金属行为$p=X>p^{*}～0.19$并与非金属行为对比$p<p^{*}$。我们建议更改于$p^{*}$与从掺杂莫特绝缘体到传统金属的一阶跃迁相关；由于内在的掺杂无序，该转变表现为交叉。我们考虑了支持这一观点的文献结果；特别是，我们模拟了无序对一阶跃迁的影响以及条纹相关性的掺杂依赖性。以下$p^{*}$，强电子相互作用导致电荷和自旋条纹相关性渗透到整个${\mathrm{氧化铜}}_2$飞机；多于$p^{*}$，残余条纹相关性仅限于孤立的水坑。我们建议$\mathrm{时间}$-线性电阻率是由相关水坑内的反铁磁自旋波动引起的准粒子散射产生的。与以下情况相比，这是一个适度的影响$p<p^{*}$，其中数据表明正常状态下不存在相干准粒子。