Pseudospin-controlled optical Bloch oscillations in a synthetic magnetic lattice

We report theoretically polarization-controlled Bloch oscillations in the synthetic two-level photonic system, where the horizontal and vertical polarizations of light emulate pseudospin up and down. We synthesize a magnetic lattice in the light-crystal interaction process and demonstrate directional Bloch oscillations of polarized light, accompanied by the optical Zener tunneling. Within this framework, we study the directional Bloch oscillations with pure spin-up and spin-down, as well as mixing spin, carried by the fundamental Gaussian mode. Furthermore, our formulism can be extended to the higher-order framework, realizing the Bloch oscillation of the topological spin texture. These results show that the Bloch oscillation can be effectively controlled by the incident spin (polarization). We therefore anticipate that the presented framework for the Bloch oscillations can find potential applications. For example, it can be exploited as a polarization-related device for optical information processing.