Leonforte Luca, Carollo Angelo, Ciccarello Francesco
Università degli Studi di Palermo, Dipartimento di Fisica e Chimica-Emilio Segrè, via Archirafi 36, I-90123 Palermo, Italy.
Radiophysics Department, National Research Lobachevsky State University of Nizhni Novgorod, 23 Gagarin Avenue, Nizhni Novgorod 603950, Russia.
Phys Rev Lett. 2021 Feb 12;126(6):063601. doi: 10.1103/PhysRevLett.126.063601.
We identify a class of dressed atom-photon states forming at the same energy of the atom at any coupling strength. As a hallmark, their photonic component is an eigenstate of the bare photonic bath with a vacancy in place of the atom. The picture accommodates waveguide-QED phenomena where atoms behave as perfect mirrors, connecting in particular dressed bound states (BSs) in the continuum with geometrically confined photonic modes. When applied to photonic lattices, the framework establishes a one-to-one correspondence between topologically robust dressed states and topologically robust photonic BSs seeded by a vacancy. This is used to predict new classes of dressed BSs in the photonic Creutz-ladder and Haldane models. In the latter case, states with nonzero local photon flux occur in which an atom is dressed by a photon orbiting around it.
我们识别出一类在任意耦合强度下于原子相同能量处形成的缀饰原子 - 光子态。其标志在于，它们的光子成分是裸光子库的本征态，其中原子位置出现一个空位。该图景涵盖了波导量子电动力学现象，其中原子表现为完美镜面，特别地将连续统中的缀饰束缚态（BSs）与几何受限的光子模式相联系。当应用于光子晶格时，该框架在拓扑稳健的缀饰态与由空位引发的拓扑稳健的光子BSs之间建立了一一对应关系。这被用于预测光子克里茨梯和霍尔丹模型中的新型缀饰BSs。在后一种情况下，会出现具有非零局部光子通量的态，其中一个原子被围绕它轨道运行的光子所缀饰。
