论文标题
可调的手性对称性破坏对称的Weyl材料
Tunable chiral symmetry breaking in symmetric Weyl materials
论文作者
论文摘要
具有固有手性结构的不对称Weyl半法具有不同的能量和分散关系，用于左手和右手的费米子。它们表现出在对称的Weyl半法中发现的某些效果，例如量化的圆形光钙化效应和螺旋磁效应。在这项工作中，我们通过在对称的Weyl半法中应用外部场来得出破坏手性对称性所需的条件。我们明确证明，在具有$ t_d $点组的某些材料中，沿低对称方向的磁场打破了左手和右手费米子之间的对称性。可以通过更改磁场的方向和大小来调节对称性破裂。在某些情况下，我们发现I型左手和右手锥的数量之间存在不平衡（这是由每种手性的II型锥数量补偿的）。
Asymmetric Weyl semimetals, which possess an inherently chiral structure, have different energies and dispersion relations for left- and right-handed fermions. They exhibit certain effects not found in symmetric Weyl semimetals, such as the quantized circular photogalvanic effect and the helical magnetic effect. In this work, we derive the conditions required for breaking chiral symmetry by applying an external field in symmetric Weyl semimetals. We explicitly demonstrate that in certain materials with the $T_d$ point group, magnetic fields along low symmetry directions break the symmetry between left- and right-handed fermions; the symmetry breaking can be tuned by changing the direction and magnitude of the magnetic field. In some cases, we find an imbalance between the number of type I left- and right-handed Weyl cones (which is compensated by the number of type II cones of each chirality.)
