The chiral anomaly, screening and low energy electron dynamics of Weyl semimetals

魏尔半金属是最近发现的一类具有前所未有的性质的材料。作为石墨烯的三维类似物，它们显示出带有手性准粒子的整体狄拉克电子和非常大的电子迁移率，即使在室温下也是如此。狄拉克态还会在外加磁场和电场中产生强烈的等离子体效应和其他有趣的性质。这些Adler-Bell-Jackiw或手征反常现象目前被研究作为未来传感或电子学的关键元件的应用。这项建议致力于利用电子拉曼散射研究TAAS中的手性反常，以实现对低能动力学以及屏蔽和高迁移率的相互作用的详细了解。我们的数据分析是基于碰撞主导的散射机制，这对于具有强准粒子相互作用的系统是一种有效的方法。此外，我们遵循基于光学传导性到电子拉曼散射的映射的微观模型。我们以前对拓扑绝缘体的研究表明，导出的散射率与在THz吸收实验中观察到的狄拉克等离子体很好地吻合，并且计算的信号的光谱形状符合我们的理论方法。我们的项目致力于改进对相关散射过程和Weyl半金属固有的手征反常的微观理解。

Weyl semimetals are a recently discovered class of materials with unprecedented properties. As a three-dimensional analogue to graphene they exhibit Dirac electrons in the bulk with chiral quasiparticles and an extraordinarily large electronic mobility even at room temperature. The Dirac states also give rise to strong plasmonic effects and other interesting properties in applied magnetic and electric fields. These Adler-Bell-Jackiw or chiral anomalies are presently investigated with respect to applications as key elements of future sensorics or electronics. This proposal is devoted the investigation of chiral anomalies in TaAs using electronic Raman scattering to achieve a detailed understanding of low energy dynamics and the interplay of screening and high mobility. Our data analysis is based on the regime of collision dominated scattering which is an effective approach for systems with strong quasiparticle interactions. Furthermore we follow a microscopic modelling based on a mapping of optical conductivity to electronic Raman scattering. Our previous studies of topological insulators have shown that the derived scattering rates agree well with Dirac plasmons observed in THz absorption experiments and that the calculated spectral shape of the signal follows our theoretical approach. Our project is geared towards an improved microscopic understanding of the relevant scattering processes and the chiral anomaly inherent to Weyl semimetals.