标题： 光子晶格中的无反射和不可见势场 显示英文标题

标题： Reflectionless and invisible potentials in photonic lattices

摘要： 在离散光子晶格上，一个任意形状的光学势，其横向漂移速度大于晶格带的光锥所允许的最大速度，将变得无反射。 这种引人入胜的结果源于晶格的离散平移对称性，这是离散光特有的现象，在连续光学介质中的光散射中没有对应情况。 一种漂移的克雷默-克朗尼奇类型的非厄米光学势也是一种隐形势，即： 离散光学束穿过漂移势时不会被扭曲、延迟或提前。 显示英文摘要

摘要： An arbitrarily-shaped optical potential on a discrete photonic lattice, which transversely drifts at a speed larger than the maximum one allowed by the light cone of the lattice band, becomes reflectionless. Such an intriguing result, which arises from the discrete translational symmetry of the lattice, is peculiar to discretized light and does not have any counterpart for light scattering in continuous optical media. A drifting non-Hermitian optical potential of the Kramers-Kronig type is also an invisible potential, i.e. a discrete optical beam crosses the drifting potential without being distorted, delayed nor advanced.