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

arXiv:1102.4731

High reflection emission assisted by phase compensation via anomalous dispersion

Haitao Zhou, Miaojun Guo, Dawei Wang, Junxiang Zhang, Shi‐Yao Zhu

Published Feb 23, 2011• 0 citations
arXivHTMLPDF

Abstract

The reflection spectrum of a probe light in a -type three-level atomic system coupled by an off-resonant standing-wave is investigated experimentally and theoretically. We show that the maximum value of reflection coefficient occurs when both of the coupling and probe lights are tuned off resonances from the atomic transitions. The nature of enhanced reflection is attributed to the phase compensation caused by the anomalous dispersion, which leads to a significant reduction of nonlinear phase mismatch in atomic four-wave mixing. At certain detuning of coupling and probe frequencies near two-photon resonance, there exits a best compensation, so the reflection efficiency reaches its maximum. The dependences of efficiency on the intensity of coupling fields and the density of atoms are also studied.

DOI
10.48550/arxiv.1102.4731

Related papers

Enhanced reflection via phase compensation from anomalous dispersion in atomic vapor

Jun-Xiang Zhang, Hai Tao Zhou, Dawei Wang +1 more

The phase compensation mechanism induced by anomalous dispersion in the reflection process of four-wave mixing (or reflection from a grating) in a three-level system is investigated, where the four wave vectors do not match in vacuum. An efficiency of the reflected signal of as high as 43% from a hot atomic cell of Cs is observed. The maximum reflection occurs when the frequency of the probe beam (and consequently the frequency of the reflected signal) is slightly red detuned from the transition frequency, which is attributed to the phase compensation from the steep anomalous dispersion accompanied with a strong probe absorption. The dependences of the efficiency on the angle between the coupling and probe lights, on the intensity of the coupling, field and on atomic density are studied. A theoretical model is presented and it is in good agreement with the experimental results.

Physical Review A•May 27, 2011•45 citations

Controllable optical mirror of cesium atoms with four-wave mixing

Haitao Zhou, Dan Wang, Miao-Jun Guo +2 more

The controllable optical mirror is experimentally accomplished in a λ-type three-level atomic system coupled with standing wave. It is shown that the reflection of probe light results from electromagnetically-induced-transparency-based four-wave mixing, therefore the reflection efficiency is highly dependent on the angle for phase matching condition between the probe and coupling fields. The measured reflection spectra show good agreement with dispersion compensation theory.

Chinese Physics B•Sep 1, 2014•0 citations

Efficient reflection via four-wave mixing in a Doppler-free electromagnetically-induced-transparency gas system

Haitao Zhou, Dawei Wang, Dan Wang +2 more

We experimentally demonstrate the high-efficiency reflection of a probe field in \ensuremath{\Lambda}-type three-level atoms of cesium vapor driven by two counterpropagating coupling fields. More than 60$%$ of reflection efficiency is observed at the phase-matching angle. The underlying mechanism theoretically is investigated as the four-wave mixing is enhanced by the electromagnetically-induced transparency. Both of the two Doppler-free two-photon resonances (one for the probe and co-propagating fields, the other for the reflected and the counterpropagation fields) play an important role in satisfying the phase matching in the reflection direction. The phase compensation due to the anomalous dispersion and the decrease of effective absorption length in the atomic system allow the efficient reflection to be observed in a wide range of incident angles of the probe field and detunings of the coupling field.

Physical Review A•Nov 17, 2011•45 citations

Angular momentum and two-photon detuning dependence of reflection spectrum on degenerate two-level systems in Cs vapour

Haitao Zhou, Miaojun Guo, Dan Wang +3 more

The absorption and reflection spectrum of probe light, interacting with a degenerate two-level system of any transition in the Cs D1 line driven by standing-wave, is experimentally studied. The effect that absorption changes from a transparency dip to an absorption peak when the travelling coupling field is replaced by the standing-wave field can only occur in the hyperfine transition Fg↔Fe ≤ Fg (Fg and Fe are the total angular momentum of the ground and the excited levels respectively), and in this case, a reflection of probe can be generated. It is also examined that the absorption coefficient and reflection efficiency in the transition of Fg > Fe are much higher than that in Fg = Fe. For the transition of Fg < Fe, where coherent population trapping cannot be established, the absorption does not change the sign, and there is no reflection to be observed when the coupling is switched from a travelling to a standing-wave field. As a consequence, only the degenerate two-level systems, where the population is trapped in the ground states, can exhibit steep absorption and reflection of the probe light with a standing-wave coupling. Furthermore, the reflection spectra with an asymmetric profile as the function of one- and two-photon detunings are obtained, which is theoretically explained by the phase mismatch compensation during the process of four-wave mixing in an atomic system. This shows that under the condition of coherent population trapping the nonlinear reflection can be improved with one- and two-photon detunings in a degenerate two-level system.

Journal of Physics B Atomic Molecular and Optical Physics•Nov 1, 2011•4 citations

Superluminal reflection and transmission of light pulses via resonant four-wave mixing in cesium vapor

Qichang Jiang, Yan Zhang, Dan Wang +3 more

We report the experimental manipulation of the group velocities of reflected and transmitted light pulses in a degenerate two-level atomic system driven by a standing wave, which is created by two counter-propagating light beams of equal frequencies but variable amplitudes. It is shown that the light pulse is reflected with superluminal group velocity while the transmitted pulse propagates from subluminal to superluminal velocities via changing the power of the backward coupling field. We find that the simultaneous superluminal light reflection and transmission can be reached when the power of the backward field becomes closer or equal to the forward power, in this case the periodical absorption modulation for photonic structure is established in atoms. The theoretical discussion shows that the anomalous dispersion associated with a resonant absorption dip within the gain peak due to four-wave mixing leads to the superluminal reflection, while the varying dispersion from normal to anomalous at transparency, transparency within absorption, and electromagnetically induced absorption windows leads to the subluminal to superluminal transmission.

Optics Express•Oct 12, 2016•6 citations

Electromagnetically induced grating via amplitude and phase modulations in a three-level V-type atomic medium

Nguyen Thi Thu Hien, Nguyen Huy Bang, Bui Van Cuong +9 more

Abstract A probe laser beam can be completely absorbed in an atomic resonance frequency region, however, if a coupling laser beam is further applied to the atom, the atomic medium can exhibit electromagnetically induced transparency, i.e the probe beam can be completely transmitted through the atomic medium. Thus, if the coupling beam is a standing wave field with nodes and antinodes, it will cause in space a periodic modulation of the transmitted spectrum of the probe field. This means that the probe field propagates through the atomic medium just as it passes through a diffraction grating which is called electromagnetically induced grating. Based on amplitude or phase modulation of transmission function, the absorption grating or the phase grating can be formed, respectively. In this work, based on controllable absorption and dispersion properties of a three-level V-type atomic system, we study the control of the absorption grating and the phase grating with respect to the intensity and the frequency of the laser fields. The absorption diffraction pattern at the two-photon resonance is obtained, while the phase diffraction pattern appears when there is a frequency shift of either the coupling frequency or the probe frequency compared to the corresponding atomic resonance frequency. By adjusting the coupling or/and probe laser frequency, the absorption grating can be converted into the phase grating and the high-order diffraction efficiency can also be improved.

Journal of Optics•Sep 19, 2024•1 citation
The reflection spectrum of a probe light in a -type three-level atomic system coupled by an off-resonant standing-wave is investigated experimentally and theoretically. We show that the maximum value of reflection coefficient occurs when both of the coupling and probe lights are tuned off resonances from the atomic transitions. The nature of enhanced reflection is attributed to the phase compensation caused by the anomalous dispersion, which leads to a significant reduction of nonlinear phase mismatch in atomic four-wave mixing. At certain detuning of coupling and probe frequencies near two-photon resonance, there exits a best compensation, so the reflection efficiency reaches its maximum. The dependences of efficiency on the intensity of coupling fields and the density of atoms are also studied.
The phase compensation mechanism induced by anomalous dispersion in the reflection process of four-wave mixing (or reflection from a grating) in a three-level system is investigated, where the four wave vectors do not match in vacuum. An efficiency of the reflected signal of as high as 43% from a hot atomic cell of Cs is observed. The maximum reflection occurs when the frequency of the probe beam (and consequently the frequency of the reflected signal) is slightly red detuned from the transition frequency, which is attributed to the phase compensation from the steep anomalous dispersion accompanied with a strong probe absorption. The dependences of the efficiency on the angle between the coupling and probe lights, on the intensity of the coupling, field and on atomic density are studied. A theoretical model is presented and it is in good agreement with the experimental results.
We experimentally demonstrate the high-efficiency reflection of a probe field in \ensuremath{\Lambda}-type three-level atoms of cesium vapor driven by two counterpropagating coupling fields. More than 60% of reflection efficiency is observed at the phase-matching angle. The underlying mechanism theoretically is investigated as the four-wave mixing is enhanced by the electromagnetically-induced transparency. Both of the two Doppler-free two-photon resonances (one for the probe and co-propagating fields, the other for the reflected and the counterpropagation fields) play an important role in satisfying the phase matching in the reflection direction. The phase compensation due to the anomalous dispersion and the decrease of effective absorption length in the atomic system allow the efficient reflection to be observed in a wide range of incident angles of the probe field and detunings of the coupling field.
The absorption and reflection spectrum of probe light, interacting with a degenerate two-level system of any transition in the Cs D1 line driven by standing-wave, is experimentally studied. The effect that absorption changes from a transparency dip to an absorption peak when the travelling coupling field is replaced by the standing-wave field can only occur in the hyperfine transition Fg↔Fe ≤ Fg (Fg and Fe are the total angular momentum of the ground and the excited levels respectively), and in this case, a reflection of probe can be generated. It is also examined that the absorption coefficient and reflection efficiency in the transition of Fg > Fe are much higher than that in Fg = Fe. For the transition of Fg < Fe, where coherent population trapping cannot be established, the absorption does not change the sign, and there is no reflection to be observed when the coupling is switched from a travelling to a standing-wave field. As a consequence, only the degenerate two-level systems, where the population is trapped in the ground states, can exhibit steep absorption and reflection of the probe light with a standing-wave coupling. Furthermore, the reflection spectra with an asymmetric profile as the function of one- and two-photon detunings are obtained, which is theoretically explained by the phase mismatch compensation during the process of four-wave mixing in an atomic system. This shows that under the condition of coherent population trapping the nonlinear reflection can be improved with one- and two-photon detunings in a degenerate two-level system.
We report the experimental manipulation of the group velocities of reflected and transmitted light pulses in a degenerate two-level atomic system driven by a standing wave, which is created by two counter-propagating light beams of equal frequencies but variable amplitudes. It is shown that the light pulse is reflected with superluminal group velocity while the transmitted pulse propagates from subluminal to superluminal velocities via changing the power of the backward coupling field. We find that the simultaneous superluminal light reflection and transmission can be reached when the power of the backward field becomes closer or equal to the forward power, in this case the periodical absorption modulation for photonic structure is established in atoms. The theoretical discussion shows that the anomalous dispersion associated with a resonant absorption dip within the gain peak due to four-wave mixing leads to the superluminal reflection, while the varying dispersion from normal to anomalous at transparency, transparency within absorption, and electromagnetically induced absorption windows leads to the subluminal to superluminal transmission.
Abstract A probe laser beam can be completely absorbed in an atomic resonance frequency region, however, if a coupling laser beam is further applied to the atom, the atomic medium can exhibit electromagnetically induced transparency, i.e the probe beam can be completely transmitted through the atomic medium. Thus, if the coupling beam is a standing wave field with nodes and antinodes, it will cause in space a periodic modulation of the transmitted spectrum of the probe field. This means that the probe field propagates through the atomic medium just as it passes through a diffraction grating which is called electromagnetically induced grating. Based on amplitude or phase modulation of transmission function, the absorption grating or the phase grating can be formed, respectively. In this work, based on controllable absorption and dispersion properties of a three-level V-type atomic system, we study the control of the absorption grating and the phase grating with respect to the intensity and the frequency of the laser fields. The absorption diffraction pattern at the two-photon resonance is obtained, while the phase diffraction pattern appears when there is a frequency shift of either the coupling frequency or the probe frequency compared to the corresponding atomic resonance frequency. By adjusting the coupling or/and probe laser frequency, the absorption grating can be converted into the phase grating and the high-order diffraction efficiency can also be improved.