论文标题
floquet-weyl半符号由光学共振的频带转换产生
Floquet-Weyl semimetals generated by an optically resonant interband-transition
论文作者
论文摘要
通过在II-V组狭窄的间隙半导体Zn $ _3 $ _2 $上照射具有左圆极化（逆时针方向旋转的连续波激光器（在逆时针方向上旋转），从理论上调查了$ _2 $的floquet-weyl半学（FWSM）（fwsm），该激光器具有左手圆极化（随时间逆时针方向旋转），从理论上调查了$ _2 $的$ _2 $。发现通过这种激光引起的晶体激发诱导了两种类型的FWSM阶段，它们在字符上绝对不同。 To be specific, the associated two pairs of Weyl points are stably formed by band touching between Floquet sidebands ascribable to a valence band labeled as $J_z=\pm3/2$ and a conduction band labeled as $J_z=\pm 1/2$, where $J_z$ represents the $z$-component of total angular momentum quantum number of $Γ$-point and a double sign corresponds. Here, one FWSM state composed of the up-spin Floquet sidebands relevant to $J_z=3/2$ and $1/2$ shows almost quadratic band-touching in the vicinity of the associated pair of Weyl points, while the other FWSM state composed of the down-spin Floquet sidebands relevant to $J_z=-3/2$ and $-1/2$ shows linear band-touching.此外，据揭示了上旋转和沿旋转的边带均寄托于非平凡的二维表面状态，这些状态被固定在各个韦尔点对上。两个表面状态也显示出不同的能量分散和物理特性。在文本中进行了更详细的讨论，介绍了上述发现的起源，FWSM阶段的手性，拓扑顺序的改变，激光诱导的磁性特性等。
Floquet-Weyl semimetals (FWSMs) generated by irradiation of a continuous-wave laser with left-hand circular polarization (rotating in counterclockwise sense with time) on the group II-V narrow gap semiconductor Zn$_3$As$_2$ are theoretically investigated, where the frequency of the laser is set nearly {\it resonant} with a band gap of the crystal. It is found that the excitation of the crystal by such a laser induce two types of FWSM phases that differ absolutely in characters. To be specific, the associated two pairs of Weyl points are stably formed by band touching between Floquet sidebands ascribable to a valence band labeled as $J_z=\pm3/2$ and a conduction band labeled as $J_z=\pm 1/2$, where $J_z$ represents the $z$-component of total angular momentum quantum number of $Γ$-point and a double sign corresponds. Here, one FWSM state composed of the up-spin Floquet sidebands relevant to $J_z=3/2$ and $1/2$ shows almost quadratic band-touching in the vicinity of the associated pair of Weyl points, while the other FWSM state composed of the down-spin Floquet sidebands relevant to $J_z=-3/2$ and $-1/2$ shows linear band-touching. Further, it is revealed that both up-spin and down-spin sidebands host nontrivial two-dimensional surface states that are pinned to the respective pairs of the Weyl points. Both surface states also show different energy dispersions and physical properties. More detailed discussion is made in the text on the origin of the above findings, chirality of the FWSM phases, alteration of topological order, laser-induced magnetic properties, and so on.
