Levy A L, Sushkov A B, Liu Fengguang, Shen Bing, Ni Ni, Drew H D, Jenkins G S
Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, Maryland 20742, USA.
National Institute of Standards and Technology (NIST), Gaithersburg, Maryland 20899, USA.
Phys Rev B. 2020;101(12). doi: 10.1103/physrevb.101.125102.
Chiral pumping from optical electric fields oscillating at terahertz frequencies is observed in the Weyl material TaAs with electric and magnetic fields aligned along both the and axes. Free-carrier spectral weight enhancement is measured directly, confirming theoretical expectations of chiral pumping. A departure from linear field dependence of the Drude weight is observed at the highest fields in the quantum limit, providing evidence of field-dependent Fermi velocity of the chiral Landau level. Implications for the chiral magnetic effect in Weyl semimetals from the optical -sum rule are discussed.
在具有沿(x)轴和(y)轴对齐的电场和磁场的外尔材料TaAs中，观察到了由太赫兹频率振荡的光电场产生的手性泵浦。直接测量了自由载流子光谱权重增强，证实了手性泵浦的理论预期。在量子极限下的最高场中观察到德鲁德权重偏离线性场依赖性，这为手性朗道能级的场依赖费米速度提供了证据。讨论了光学和规则对外尔半金属中手性磁效应的影响。
