Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Nonlinear index-enhancement and laser propagation in a four-level Raman-driven system

W.W. Dostalik

Published Nov 1, 1997• 0 citations
OpenAlex

Related papers

Effect of finite bandwidths of probe and driving fields on refractive index and gain in a Raman-driven four-level system

Hanzhuang Zhang, Jin-Yue Gao

Zeitschrift für Physik D Atoms Molecules and Clusters•Mar 1, 1996•3 citations

Theoretical analysis of a four-level laser without inversion driven by a pulsed Raman field

Heide Doss, Lorenzo M. Narducci, Marlan O. Scully +1 more

Optics Communications•Jan 1, 1993•25 citations

Physical origin of the gain in a four-level model of a Raman driven laser without inversion

Lorenzo M. Narducci, Marlan O. Scully, Christoph H. Keitel +2 more

Optics Communications•Nov 1, 1991•96 citations

Coupler-free surface polariton excitation and propagation with cold four-level atomic medium

Saeid Asgarnezhad-Zorgabad, Rasoul Sadighi‐Bonabi, Chao Hang

The possibility of the direct excitation of surface polaritons (SPs) by the free-space laser fields at the interface of negative-index metamaterial (NIMM) layer and a bottom layer of cold double Lambda-type atomic medium is investigated. The giant field enhancement (up to |E/E0|2≈4.1), together with suppressed ohmic loss of the NIMM layer in a wide transparency window of a double electromagnetically induced transparency, results in the SPs generation. The excitation efficiency of these SPs can be effectively enhanced by applying the unidirectional atomic motion, modulation of the coupling laser characteristics, and using a probe laser with proper incident angle. Based on the special modulation of the driven fields parameters, the group velocity switching of the SPs is observed. In the nonlinear propagation regime of the SPs, a giant Kerr nonlinearity is produced by applying a negative unidirectional atomic velocity. The controllable optical Kerr effect in this coupler-free scheme results in the lossless propagation of the nonlinear SPs. It is revealed that the electromagnetically induced transparencybased system can be used for stable propagation of one-dimensional (1+1)D bright and dark superluminal polaritonic solitons. It is also shown that the proposed scheme could be easily realized in an experiment and hence can be used for various ultrafast optical devices.

Journal of the Optical Society of America B•Aug 2, 2017•12 citations

Lasing Without Inversion In A Four-level Raman System

Rai, Wang, Izatt

Quantum Electronics and Laser Science Conference•Jan 1, 1997•0 citations

High-order nonlinear Schrödinger equation and weak-light superluminal solitons in active Raman gain media with two control fields

Chengjie Zhu, Guoxiang Huang

We propose a scheme to generate superluminal optical solitons in a four-level atomic system with two control fields via an active Raman gain. We derive a modified nonlinear Schrödinger equation with high-order corrections contributed from linear and differential absorption, nonlinear dispersion, and delay response of nonlinear refractive index of the system. We predict various optical solitons in different regimes of system parameters, and show that these optical solitons have superluminal propagating velocity and very low generation power.

Optics Express•Jan 19, 2011•15 citations
The possibility of the direct excitation of surface polaritons (SPs) by the free-space laser fields at the interface of negative-index metamaterial (NIMM) layer and a bottom layer of cold double Lambda-type atomic medium is investigated. The giant field enhancement (up to |E/E0|2≈4.1), together with suppressed ohmic loss of the NIMM layer in a wide transparency window of a double electromagnetically induced transparency, results in the SPs generation. The excitation efficiency of these SPs can be effectively enhanced by applying the unidirectional atomic motion, modulation of the coupling laser characteristics, and using a probe laser with proper incident angle. Based on the special modulation of the driven fields parameters, the group velocity switching of the SPs is observed. In the nonlinear propagation regime of the SPs, a giant Kerr nonlinearity is produced by applying a negative unidirectional atomic velocity. The controllable optical Kerr effect in this coupler-free scheme results in the lossless propagation of the nonlinear SPs. It is revealed that the electromagnetically induced transparencybased system can be used for stable propagation of one-dimensional (1+1)D bright and dark superluminal polaritonic solitons. It is also shown that the proposed scheme could be easily realized in an experiment and hence can be used for various ultrafast optical devices.
We propose a scheme to generate superluminal optical solitons in a four-level atomic system with two control fields via an active Raman gain. We derive a modified nonlinear Schrödinger equation with high-order corrections contributed from linear and differential absorption, nonlinear dispersion, and delay response of nonlinear refractive index of the system. We predict various optical solitons in different regimes of system parameters, and show that these optical solitons have superluminal propagating velocity and very low generation power.