Open AccessGiant Kerr nonlinearity and weak-light superluminal optical solitons in a four-state atomic system with gain doublet
Author(s) -
Chao Hang,
Guoxiang Huang
Publication year - 2010
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.18.002952
Subject(s) - superluminal motion , electromagnetically induced transparency , physics , kerr effect , optics , cross phase modulation , distortion (music) , interference (communication) , quantum optics , group velocity , slow light , magneto optic kerr effect , attenuation , self phase modulation , nonlinear optics , nonlinear system , phase modulation , laser , quantum mechanics , phase noise , optoelectronics , photonic crystal , telecommunications , amplifier , channel (broadcasting) , cmos , computer science
We consider an active-Raman-gain scheme for realizing giant Kerr nonlinearity and superluminal optical solitons in a four-state atomic system with a gain doublet. We show that this scheme, which is fundamentally different from those based on electromagnetically induced transparency (EIT), is capable of working at room temperature and eliminating nearly all attenuation and distortion.We demonstrate that, due to the appearance of a gain spectrum hole induced by the quantum interference effect induced by a signal field, a significant enhancement of Kerr nonlinearity of probe field can be realized effectively, which can be more than ten times larger than that arrived by the EIT-based scheme with the same energy-level configuration. Based on these important features, we obtain a giant cross-phase modulation effect and hence a stable long-distance propagation of optical solitons, which have superluminal propagating velocity and very low generating power.