论文标题
紧张的CD3AS2拓扑半学中增强的Dirac节点分离
Enhanced Dirac node separation in strained Cd3As2 topological semimetal
论文作者
论文摘要
在拓扑半学中，由于带反转，节点出现在布里渊区的对称点上，并在低能量下产生准准论的无质量质量费米子。 CD3AS2是一种三维拓扑半学，容纳两个负责各种量子现象的狄拉克锥。在这项工作中，我们通过在外延膜上进行的磁性红外光谱和高分辨率的X射线衍射研究的结合来证明CD3AS2的DIRAC节点的应变调整。在这些薄膜中，我们观察到动量空间中节点分离的巨大增强，接近4倍。实验测量和理论建模的结合使得这种增强的起源与加强由lattice菌株驱动的拓扑带反演。我们的结果表明，如何将应变用作旋钮来调整半学的拓扑特性，并有可能提高其对各种应用的性能和响应。
In topological semimetals, nodes appear at symmetry points in the Brillouin zone as a result of band inversion, and yield quasi-relativistic massless fermions at low energies. Cd3As2 is a three-dimensional topological semimetal that hosts two Dirac cones responsible for a variety of quantum phenomena. In this work, we demonstrate the strain tuning of the Dirac nodes of Cd3As2 through a combination of magnetooptical infrared spectroscopy and high-resolution X-ray diffraction studies performed on epitaxial films. In these thin films, we observe a giant enhancement of the node separation in momentum space by close to a factor of 4. A combination of experimental measurements and theoretical modelling allows relate the origin of this enhancement to a strengthening of the topological band inversion driven by lattice strain. Our results demonstrate how strain can be used as a knob to tune the topological properties of semimetals and to potentially enhance their performance and response for various applications.
