Time Circular Birefringence in Time-Dependent Magnetoelectric Media.
Light traveling in time-dependent media has many extraordinary properties which can be utilized to convert frequency, achieve temporal cloaking, and simulate cosmological phenomena. In this paper, we focus on time-dependent axion-type magnetoelectric (ME) media, and prove that light in these media always has two degenerate modes with opposite circular polarizations corresponding to one wave vector , and name this effect "time circular birefringence" (TCB). By interchanging the status of space and time, the pair of TCB modes can appear simultaneously via "time refraction" and "time reflection" of a linear polarized incident wave at a time interface of ME media. The superposition of the two TCB modes causes the "time Faraday effect", namely the globally unified polarization axes rotate with time. A circularly polarized Gaussian pulse traversing a time interface is also studied. If the wave-vector spectrum of a pulse mainly concentrates in the non-traveling-wave band, the pulse will be trapped with nearly fixed center while its intensity will grow rapidly. In addition, we propose an experimental scheme of using molecular fluid with external time-varying electric and magnetic fields both parallel to the direction of light to realize these phenomena in practice.
Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin, 300071, China.|Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Ruo-Yang
RY
Zhang
School of Physics, Beijing Institute of Technology, Beijing, 100081, China.
Yan-Wang
YW
Zhai
School of Physics, Beijing Institute of Technology, Beijing, 100081, China.
Shi-Rong
SR
Lin
School of Physics, Beijing Institute of Technology, Beijing, 100081, China.
Qing
Q
Zhao
Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Weijia
W
Wen
Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin, 300071, China.|School of Physics, Beijing Institute of Technology, Beijing, 100081, China.
Mo-Lin
ML
Ge