Ultraslow temporal vector optical solitons in a cold four-level tripod atomic system

Abstract

We show the possibility of generating ultraslow temporal vector optical solitons in a cold lifetime-broadened four-level tripod atomic medium under Raman excitation. We demonstrate that the two orthogonally polarized components of the low-intensity signal field can evolve into various distortion-free temporal vector optical solitons, such as bright-bright vector solitons with ultraslow group velocity. These results are produced from the balance of self- and cross-phase modulation effects and dispersion. We also show that Manakov temporal vector solitons may be realized by adjusting the corresponding self- and cross-phase modulation and dispersion effects of our system.