论文标题
klein隧道在变形$α-t_3 $ lattice中
Klein tunneling in deformed $α-T_3$ lattice
论文作者
论文摘要
通过在$α-T_3 $晶格上应用压缩的单轴变形，该晶格在蜂窝晶格（$α= 0 $）和骰子晶格（$α= 1 $）之间进行插值，Dirac锥，沿给定的方向和差距开路，而平面频段则保持不变。因此，沿着该合并方向的低能光谱表现出从狄拉克相的线性分散体到间隙相位的二次色散的过渡。但是，沿垂直方向，光谱保持线性。在这里，我们从理论上通过$ \ mathit {np} $连接在变形的$α-T_3 $ lattice中研究粒子的隧道特性。在Dirac阶段，我们发现隧道属性与未完整的$α-T_3 $晶格的隧道属性相似，例如以正常发病率的$α$的完美klein隧道和交界处的总透明度，即超级klein隧道的总透明度，即$ a = 1 $ n时$ a = 1 $ n时，能量等于一半。在差距阶段，当连接处垂直于变形方向时，我们会获得相反的行为，在这些方向上，完美的克莱因隧道变成了所有参数$α$的反klein隧道效应，而超级克莱因隧道隧道效果转换为抗柔软的klein隧道效应，即完全是opaque。
By applying a compressive uniaxial deformation on the $α-T_3$ lattice, which interpolates between honeycomb lattice ($α=0$) and dice lattice ($α=1$), the Dirac cones move toward each other along a given direction, merge and a gap opens while the flat band remains unchanged. Therefore, the low-energy spectrum, along this merging direction, exhibits a transition from a linear dispersion in the Dirac phase to a quadratic dispersion in the gapped phase. However, along the perpendicular direction the spectrum remains linear. Here we theoretically study the tunneling properties of particles through a $\mathit{np}$ junction in deformed $α-T_3$ lattice. In the Dirac phase, we find that the tunneling properties are similar to those of undeformed $α-T_3$ lattice such as the perfect Klein tunneling at normal incidence for all values of $α$ and the total transparency of the junction, i.e. the super-Klein tunneling, for $α=1$ when the energy is equal to half of the junction height. In the gapped phase, we obtain an opposite behavior when the junction is oriented perpendicular to the deformation direction where the perfect Klein tunneling turns into the anti-Klein tunneling effect for all parameters $α$ and the super-Klein tunneling effect transits to the anti-super Klein tunneling effect, i.e. the junction is totally opaque.
