论文标题
磁转运和全息金属绝缘体过渡的复杂性
Magnetotransport and Complexity of Holographic Metal-Insulator Transitions
论文作者
论文摘要
我们研究了两个空间维度的金属 - 绝缘体跃迁的最小全息设置中的磁转移。获得了一些通用特征，而无需参考全息理论的非线性细节。发现电阻率的温度依赖性已通过单个参数$ t_0 $进行了很好的缩放，该参数以某种关键充电密度$ρ_C$的零接近零，并且随着电力定律的增加而增加，$ t_0 \ sim | p_0 \ sim |ρ_C|^{1/2} $ in Metallic $（ρ>ρ_C）$（ρ>ρ_C）$（ρ_c）$（ρ_C）$（c）类似的特征也通过改变障碍强度和磁场来实现。通过在存在的磁场存在下需要正确定的纵向电导率，可以限制理论参数的允许参数空间。我们明确检查了两个代表性模型的参数范围的一致性，并计算金属和绝缘阶段的光电电导率，从中，疾病诱导的光谱从低能向高能转移。我们在温度和无序强度方面构建相图。研究了过渡过程中的复杂性，并发现对金属 - 绝缘体过渡不是很好的探针。
We study the magnetotransport in a minimal holographic setup of a metal-insulator transition in two spatial dimensions. Some generic features are obtained without referring to the non-linear details of the holographic theory. The temperature dependence of resistivity is found to be well scaled with a single parameter $T_0$, which approaches zero at some critical charge density $ρ_c$, and increases as a power law $T_0\sim|ρ-ρ_c|^{1/2}$ both in metallic $(ρ>ρ_c)$ and insulating $(ρ<ρ_c)$ regions in the vicinity of the transition. Similar features also happen by changing the disorder strength as well as magnetic field. By requiring a positive definite longitudinal conductivity in the presence of an applied magnetic field restricts the allowed parameter space of theory parameters. We explicitly check the consistency of parameter range for two representative models, and compute the optical conductivities for both metallic and insulating phases, from which a disorder-induced transfer of spectral weight from low to high energies is manifest. We construct the phase diagram in terms of temperature and disorder strength. The complexity during the transition is studied and is found to be not a good probe to the metal-insulator transition.
