论文标题
拓扑光子相的浆果带和伪旋转
Berry bands and pseudo-spin of topological photonic phases
论文作者
论文摘要
实现鲁棒，单向边缘状态的光子类似物，将改善我们对纳米级的光的控制，并彻底改变光子设备的性能。在这里，我们表明，可以通过将能量本本特征标记为浆果曲率本本特征问题来检测到新的对称性保护拓扑阶段。 “浆果乐队”与原始价能频带跨越相同的特征空间，但在$ \ mathrm {c} _2 _2 \ mathcal {t} $ - 对称晶体中分为伪固定和伪无形子空间。我们演示了有关Wu＆Hu [Phys的众所周知案例的方法。莱特牧师。 114，223901（2015）]和一个最近发现的厚实拓扑结晶，并表明两个晶体都属于相同的$ \ mathrm {c} _2 _2 \ mathcal {t} $ - 受保护的$ \ mathbb {z} _2 _2 _2 _2 _2 $拓扑阶段。这项工作有助于统一理论和数字，并有助于定义和识别光子学和电子学中新的受对称保护阶段。
Realising photonic analogues of the robust, unidirectional edge states of electronic topological insulators would improve our control of light on the nanoscale and revolutionise the performance of photonic devices. Here we show that new symmetry protected topological phases can be detected by reformulating energy eigenproblems as Berry curvature eigenproblems. The "Berry bands" span the same eigenspace as the original valence energy bands, but separate into pseudo-spinful and pseudo-spinless subspaces in $\mathrm{C}_2\mathcal{T}$-symmetric crystals. We demonstrate the method on the well-known case of Wu & Hu [Phys. Rev. Lett. 114, 223901 (2015)] and a recently discovered fragilely topological crystal, and show that both crystals belong to the same $\mathrm{C}_2\mathcal{T}$-protected $\mathbb{Z}_2$ topological phase. This work helps unite theory and numerics, and is useful in defining and identifying new symmetry-protected phases in photonics and electronics.
