Affiliation:
1. State Academy of Sciences Institute of Physics Unjong District, PO Box 355 Pyongyang, Democratic People's Republic of Korea
Abstract
The concept of photonic crystals has recently been extended to the time domain and attracted great interest. Unfortunately, realizing photonic time crystals is a challenging task due to the practical difficulty in modulating dielectric constants with large modulation depth. This problem can be resolved using graphene, the conductivity of which is tunable with significantly large contrast. Herein, graphene plasmonic time crystals, as new kinds of photonic time crystals in atomically thin 2D material, are proposed and their optical properties are investigated. Their band structures are analytically calculated and the propagations of graphene plasmons in temporal crystalline structures are numerically evaluated. Periodically driven by temporally modulating the Fermi energy, graphene plasmons exhibit in‐gap amplification and defect‐immune topological edge states, revealing the nature as plasmonic time crystals. Graphene plasmonic time crystals are realized soon after this proposal due to the possibility of modulating its conductivity with large contrast by simple electrical gating.