论文标题
基于$ a $ a $ bi $ _ {2} $的Laves阶段的三次系统中的手性声子（$ a = $ k，rb，cs）
Chiral phonon in the cubic system based on the Laves phase of $A$Bi$_{2}$ ($A=$K, Rb, Cs)
论文作者
论文摘要
$ a $ b $ _ {2} $（$ a = $ k，rb，cs）化合物在立方薰衣草阶段结晶（对称fd $ \ bar {3} $ m）。晶体结构的几何形状允许实现手性声子，这与原子围绕其平衡位置的循环有关。由于反转对称性和时间逆转对称性，系统的总伪角动量（PAM）消失了。我们表明，这些系统的掺杂可以导致一个新阶段，并具有对称性f $ \ bar {4} 3 $ m。新系统（krbbi $ _ {4} $和rbcsbi $ _ {4} $）不表现出软模式（动态稳定）。由于反转对称性破坏，实现的手性声子模式具有非零的总PAM。在两种类型的系统中，手性声子都是为Brillouine区域边缘的波射线实现的。这项研究探讨了通过掺杂的手性声子工程的可能性，并预测了两种新材料。讨论该问题开辟了一种研究声子效应的新方法。
$A$B$_{2}$ ($A=$K, Rb, Cs) compounds crystallize in the cubic Laves phase (symmetry Fd$\bar{3}$m). The geometry of the crystal structure allows the realization of chiral phonons, which are associated with the circulation of atoms around their equilibrium positions. Due to the inversion symmetry and time reversal symmetry, total pseudo-angular momentum (PAM) of the system vanishes. We show that the doping of these system can lead to a new phase with symmetry F$\bar{4}3$m. New systems (KRbBi$_{4}$ and RbCsBi$_{4}$) do not exhibit soft modes (are stable dynamically). Due to the inversion symmetry breaking, realized chiral phonon modes posses a non-zero total PAM. In both type of systems the chiral phonons are realized for the wavectors at the edge of the Brillouine zone. This study explores the possibility of chiral phonon engineering via doping, and predicts two new materials. Discussing the problem opens a new way to study the phonon Hall effect.
