论文标题
2D半导体系统的Planckian特性
Planckian properties of 2D semiconductor systems
论文作者
论文摘要
我们从普兰克假设的角度来描述并讨论了几种不同掺杂的2D半导体系统的低温电阻率（以及温度依赖性的非弹性散射率），声称$ \ hbar/τ= k__ \ k__ \ mathrm {b} t $提供了适当的散射bound bound $τ$。这里考虑的运输状态是Bloch-Gruneisen制度的良好，因此声子散射可以忽略不计。电阻率的温度依赖性部分几乎是在任意低温度下的线性 - $ t $降低，而线性是由筛选和无序之间的相互作用引起的，与杂质诱导的弗里德尔振荡的载体散射有关。如果抑制了电子之间的库仑相互作用，温度依赖性消失。电阻率的温度系数在较低的密度下增强，从而详细研究了普朗克行为是材料系统和载体密度的函数。尽管确切的普朗克界限从未实现，但我们发现界限似乎与散射速率大约适用于$ k_ \ mathrm {b} t $的散射速率超过实验或理论中的数量级。此外，我们通过获得库仑相互作用而产生的温度依赖性的自我能量来计算温度依赖的电子电子非弹性散射率，也发现它在所有密度和温度下都要在数量级内服从Planckian。我们介绍了广义的普朗基界的概念，其中$ \ hbar/τ$由$αk_\ mathrm {b} t $带有$α\ sim 10 $左右的$αk_\ mathrm {b} t $，在超级普兰科（Super-Planckian）政权中，严格的planckian政权与严格的$α$ = 1的严格限制为1 = 1是一种nongeneric fineTuned的情况。
We describe and discuss the low-temperature resistivity (and the temperature-dependent inelastic scattering rate) of several different doped 2D semiconductor systems from the perspective of the Planckian hypothesis asserting that $\hbar/τ=k_\mathrm{B}T$ provides a scattering bound, where $τ$ is the appropriate relaxation time. The regime of transport considered here is well-below the Bloch-Gruneisen regime so that phonon scattering is negligible. The temperature-dependent part of the resistivity is almost linear-in-$T$ down to arbitrarily low temperatures, with the linearity arising from an interplay between screening and disorder, connected with carrier scattering from impurity-induced Friedel oscillations. The temperature dependence disappears if the Coulomb interaction between electrons is suppressed. The temperature coefficient of the resistivity is enhanced at lower densities, enabling a detailed study of the Planckian behavior both as a function of the materials system and carrier density. Although the precise Planckian bound never holds, we find somewhat surprisingly that the bound seems to apply approximately with the scattering rate never exceeding $k_\mathrm{B} T$ by more than an order of magnitude either in the experiment or in the theory. In addition, we calculate the temperature-dependent electron-electron inelastic scattering rate by obtaining the temperature-dependent self-energy arising from Coulomb interaction, also finding it to obey the Planckian bound within an order of magnitude at all densities and temperatures. We introduce the concept of a generalized Planckian bound where $\hbar/τ$ is bounded by $αk_\mathrm{B} T$ with $α\sim 10$ or so in the super-Planckian regime with the strict Planckian bound of $α$=1 being a nongeneric finetuned situation.
