arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1401.7993hep-thcond-mat.str-el
收藏

标度不变超标度破坏全息理论与随机场无序奇异金属的电阻率

Scale-invariant hyperscaling-violating holographic theories and the resistivity of strange metals with random-field disorder

Andrew Lucas, Subir Sachdev, Koenraad Schalm

摘要:

我们计算了一个尺度不变,$d$维奇异金属的直流电阻率与动态临界指数$z$和超标度违反指数$θ$,弱扰动耦合到随机场障碍,局部打破了$\mathbb{Z}_2$对称性的标量算子。通过Einstein-Maxwell-Dilaton全息术和记忆矩阵方法的独立计算导致相同的结果。我们发现,随机场无序电阻率有很强的影响:载流子在红外线很容易耗尽,作为弛豫时间的动量是令人惊讶的小。在我们的全息计算过程中,我们使用了一个非平凡的标量耦合到无序标量,使我们能够研究一个强耦合的规模不变理论与$θ\ne 0$。利用全息术,我们也能够确定扰动理论崩溃的无序强度。奇怪的是,对于局部临界理论,当电阻率与熵密度成比例时,这种击穿就会发生,直到可能的对数校正。

英文摘要:

We compute the direct current resistivity of a scale-invariant, $d$-dimensional strange metal with dynamic critical exponent $z$ and hyperscaling-violating exponent $θ$, weakly perturbed by a scalar operator coupled to random-field disorder that locally breaks a $\mathbb{Z}_2$ symmetry. Independent calculations via Einstein-Maxwell-Dilaton holography and memory matrix methods lead to the same results. We show that random field disorder has a strong effect on resistivity: charge carriers in the infrared are easily depleted, as the relaxation time for momentum is surprisingly small. In the course of our holographic calculation we use a non-trivial dilaton coupling to the disordered scalar, allowing us to study a strongly-coupled scale invariant theory with $θ\ne 0$. Using holography, we are also able to determine the disorder strength at which perturbation theory breaks down. Curiously, for locally critical theories this breakdown occurs when the resistivity is proportional to the entropy density, up to a possible logarithmic correction.

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。

↑