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

Quantum Electronics

On the problem of controlled virtual refractive index

Anatolii N Oraevsky, Игорь Евгеньевич Проценко, A Botero

Published Sep 30, 2000• 1 citation
Publisher

Abstract

A method for controlling the refractive index that is based on the backward rescattering of the scattered and amplified electromagnetic waves is proposed and analysed. The resulting field is a sum of the initial (probe) wave and the rescattered wave. The effective wave number of the total wave can be varied by varying the gain. This variation in the wave number can be treated as a variation in the refractive index, although the physical properties of the medium do not change. The effective refractive index for the total wave propagating in such a device was called the virtual refractive index.

DOI
10.1070/qe2000v030n09abeh001823

Related papers

Control of the index of refraction in optically dense medium

К. А. Баранцев, A. N. Litvinov

In this work we investigate conditions of emergence and destruction of the electromagnetically induced transparency effect in the optically dense medium of atoms which are excited along closed contour of excitation by the three frequency radiation. We found the conditions under which index of refraction of the medium acquires spatial quasi-periodic dependence. It is possible to control this dependence by variation of the initial phases and intensities of the electromagnetic fields.

Journal of Physics Conference Series•Dec 19, 2013•1 citation

Coherent control of the refractive index using optical bistability

H. Aswath Babu, Harshawardhan Wanare

Refractive index and absorption experienced by a probe field propagating through a three-level atomic medium can be effectively manipulated by the bistable behavior of a control field. The probe field couples the lower transition of the atom in a ladder configuration and experiences normal or anomalous dispersion depending on the control field being in the upper or lower bistable state, respectively. We also obtain nonlinear dynamical instability in the form of periodic self-pulsing as the lower bistable branch becomes unstable, quite unlike earlier demonstrations of an unstable regime in the upper branch. Consequently, the susceptibility experienced by the probe field varies periodically in time as dictated by the control field self-pulsing.

arXiv:1209.1891•Physical Review A•Mar 19, 2013•6 citations

Resolving the wave vector and the refractive index from the coefficient of reflectance

V. U. Nazarov, Yia‐Chung Chang

We resolve the existing controversy concerning the selection of the sign of the normal-to-the-interface component of the wave vector k(z) of an electromagnetic wave in an active (gain) medium. Our method exploits the fact that no ambiguity exists in the case of a film of the active medium, since its coefficient of reflectance is invariant under the inversion of the sign of k(z). Then we show that the limit of the infinite film thickness determines a unique and physically consistent choice of the wave vector and the refractive index. Important practical implications of the theory are identified and discussed.

arXiv:0710.4388•Optics Letters•Oct 4, 2007•14 citations

Comment on “Resolving the wave vector and the refractive index from the coefficient of reflectance”

Manuel Pérez Molina, L. Carretero

In a recent Letter, the reflectance coefficient was used to resolve the sign choice of the wave vector and refractive index in active media. We argue that such a coefficient loses its physical meaning for active media (at real frequencies) when the field amplification is limited only by gain saturation. In this case, the amplitude reflectance coefficient leads to fictitious noncausal reflected fields when the backward Fourier transform is used.

Optics Letters•Aug 6, 2008•5 citations

The equivalent medium theory within the linear response region

Li‐Gang Wang

In this paper, we present the equivalent medium theory by using the linear response theory. It is found that, under the condition of the linear response, a series of different media with different refractive indices $n_{i}(ω)$ and lengths $d_{i}$ can be equivalent to an effective medium with the volume-averaged refractive index $\frac{1}{D}\sum_{i=1}^{N}n_{i}(ω)d_{i}$ and the total length $D=\sum_{i=1i}^{N}d_{i}$,where $N$ is the number of different media. Based on this equivalent theory, it is a simple but very useful method to design the effective medium with any desirable dispersion properties. As an example, we present a proposal to obtain the enhancement or reduction of the refractive index without absorption and the large dispersion without obvious absorption by assembling different linear dispersive gain and absorptive media.

arXiv:0801.4409•Jan 29, 2008•0 citations

Controlling Brewster angle via manipulation of refractive index of electromagnetically induced transparency vapor

Fei Zhuang

A new application of coherent manipulation of EIT(electromagnetically induced transparency) medium is suggested,that is controlling the Brewster angle via manipulation of refractive index of electromagnetically induced transparency vapor.The EIT atomic vapor are filled on the background of two pieces glass whose refractive index is 1.5.By manipulating the refractive index of the EIT vapor via the external control field,one can obtain the controllable Brewster angle that is sensitive to the variations of external conditions(e.g.the intensity of the control field).It is shown that Controlling the Brewster angle can be achieved by choosing the specific parameters such as the Rabi frequency of control light.

Journal of Zhejiang University of Science and Technology•Jan 1, 2012•0 citations
A method for controlling the refractive index that is based on the backward rescattering of the scattered and amplified electromagnetic waves is proposed and analysed. The resulting field is a sum of the initial (probe) wave and the rescattered wave. The effective wave number of the total wave can be varied by varying the gain. This variation in the wave number can be treated as a variation in the refractive index, although the physical properties of the medium do not change. The effective refractive index for the total wave propagating in such a device was called the virtual refractive index.
Refractive index and absorption experienced by a probe field propagating through a three-level atomic medium can be effectively manipulated by the bistable behavior of a control field. The probe field couples the lower transition of the atom in a ladder configuration and experiences normal or anomalous dispersion depending on the control field being in the upper or lower bistable state, respectively. We also obtain nonlinear dynamical instability in the form of periodic self-pulsing as the lower bistable branch becomes unstable, quite unlike earlier demonstrations of an unstable regime in the upper branch. Consequently, the susceptibility experienced by the probe field varies periodically in time as dictated by the control field self-pulsing.
We resolve the existing controversy concerning the selection of the sign of the normal-to-the-interface component of the wave vector k(z) of an electromagnetic wave in an active (gain) medium. Our method exploits the fact that no ambiguity exists in the case of a film of the active medium, since its coefficient of reflectance is invariant under the inversion of the sign of k(z). Then we show that the limit of the infinite film thickness determines a unique and physically consistent choice of the wave vector and the refractive index. Important practical implications of the theory are identified and discussed.
In this paper, we present the equivalent medium theory by using the linear response theory. It is found that, under the condition of the linear response, a series of different media with different refractive indices ni(ω)n_{i}(ω)ni​(ω) and lengths did_{i}di​ can be equivalent to an effective medium with the volume-averaged refractive index 1D∑i=1Nni(ω)di\frac{1}{D}\sum_{i=1}^{N}n_{i}(ω)d_{i}D1​∑i=1N​ni​(ω)di​ and the total length D=∑i=1iNdiD=\sum_{i=1i}^{N}d_{i}D=∑i=1iN​di​,where NNN is the number of different media. Based on this equivalent theory, it is a simple but very useful method to design the effective medium with any desirable dispersion properties. As an example, we present a proposal to obtain the enhancement or reduction of the refractive index without absorption and the large dispersion without obvious absorption by assembling different linear dispersive gain and absorptive media.
A new application of coherent manipulation of EIT(electromagnetically induced transparency) medium is suggested,that is controlling the Brewster angle via manipulation of refractive index of electromagnetically induced transparency vapor.The EIT atomic vapor are filled on the background of two pieces glass whose refractive index is 1.5.By manipulating the refractive index of the EIT vapor via the external control field,one can obtain the controllable Brewster angle that is sensitive to the variations of external conditions(e.g.the intensity of the control field).It is shown that Controlling the Brewster angle can be achieved by choosing the specific parameters such as the Rabi frequency of control light.