论文标题
无定形合金的霍尔系数：由于定位弱和电子 - 电子相互作用而引起的量子校正的临界行为和定量测试
Hall coefficient in amorphous alloys: critical behavior and quantitative test of quantum corrections due to weak localization and electron-electron interactions
论文作者
论文摘要
在这里，我们在一系列$ ti_xsi_ {100-x} $无定形的一系列中介绍$ r_h $的测量值，达到关键浓度，$ x_c \ oft9-9.5 $。对于$ x \ geq17 $，霍尔系数显示了扰动理论预测的行为，$ r_h^{ - 1} \ left（t \ right）= r_h^{ - 1} \ left（0 \右）+bt^{1/2} $，它扩展到温度150 k. $ nperive $ nperive $ nperive $ pers $ npers $ solte $ solte $ solte $ gers ins ins in post in post in post in post in post y。 $ r_h \ left（0 \右）$在$ x_c $显示关键行为的情况下脱离。我们使用了具有高Ti含量的合金的组合电导率和HALL系数数据来测试量子校正的电导率理论。我们发现，由于弱定位而引起的校正是由电子 - 音波散射所主导的，其速率随温度而变化为$τ_{ep}^{ - 1} = a__ {ep} t^2 $。提取的参数$ a_ {ep} $与认为通过晶格振动的杂质不完全阻力的理论非常吻合。发现从弱定位校正中提取的自旋轨道散射时间比标准估计$τ_{so} \ oft y左（\ hbar c/e^2z \ right）^4 $的时间大两个数量级。使用HALL系数和特定的热数据对Ti-Si和$ \ left（AG_ {0.5} Cu_ {0.5} \ right）_ {100-X} ge_x $无态合金测试了EEI量子校正的理论。我们发现，在测量的准确性中，EEI理论完全适用于遵循免费电子模型[$ \ left（ag_ {0.5} cu_ {0.5} cu_ {0.5} \ right）_ {100-x} ge_x} ge_x $与$ x \ le50 $的偏离。 $ x \ geq60 $可以通过削弱系统中的电子筛选来定性解释。
Here, we present the measurements of $R_H$ in a series of $Ti_xSi_{100-x}$ amorphous reaching the critical concentration, $x_c\approx9-9.5$. For $x\geq17$, the Hall coefficient displays the behavior predicted by the perturbation theory, $R_H^{-1}\left(T\right)=R_H^{-1}\left(0\right)+bT^{1/2}$, which extends up to the temperature 150 K. The temperature dependence gets stronger in alloys with lower $x$; $R_H\left(0\right)$ diverges at $x_c$ displaying critical behavior. We used the combined conductivity and Hall coefficient data for alloys with high Ti content to test the theories of quantum corrections to conductivity. We found that the correction due to weak localization is dominated by the electron-phonon scattering with the rate varying with temperature as $τ_{ep}^{-1}=A_{ep}T^2$. The extracted parameter $A_{ep}$ is in good agreement with the theory that considers the incomplete drag of impurities by lattice vibrations. The spin-orbit scattering time extracted from the weak localization correction was found to be two orders of magnitude larger than the time given by the standard estimate $τ_{so}\approxτ\left(\hbar c/e^2Z\right)^4$. The theory of the EEI quantum correction was tested using the Hall coefficient and specific heat data for Ti-Si and $\left(Ag_{0.5}Cu_{0.5}\right)_{100-x}Ge_x$ amorphous alloys, which allowed us to estimate all microscopic parameters needed by the theory. We found that, within the accuracy of our measurements, the EEI theory works exactly for alloys that follow the free electron model [$\left(Ag_{0.5}Cu_{0.5}\right)_{100-x}Ge_x$ with $x\le50$.] The deviation from the theory observed in all Ti-Si alloys and in Ag-Cu-Ge alloys with $x\geq60$ can be qualitatively explained by weakening of the electron screening in the systems.
