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

Journal of Physics B Atomic Molecular and Optical Physics

Role of transfer of coherence in the enhanced absorption Hanle effect with two optical fields

Nibedita Ram, J. Anupriya, M. Pattabiraman, Cherianath Vijayan

Published Aug 14, 2009• 2 citations
Publisher

Abstract

The enhanced absorption Hanle effect has been studied for a closed transition Jg = 2 → Je = 3 with a transverse magnetic field in the presence of a coupling optical field. From an analysis of the individual probe and coupling field absorption profiles, it is shown that the Hanle electromagnetically induced absorption is governed by the transfer of Δm = ±2 and Δm = ±1 Zeeman coherences from the excited state to the ground state via spontaneous emission. The individual coherence contributions are governed by the intensity ratio of the optical fields. We show by computation and experiment that the magnetic field dependence of the forward scattered intensity can be used to distinguish the transfer of coherence contributions to the Hanle profile.

DOI
10.1088/0953-4075/42/17/175504

Related papers

Effect of ellipticity on Hanle electromagnetically induced absorption and transparency resonances with longitudinal and transverse magnetic fields

Nibedita Ram, M. Pattabiraman, Cherianath Vijayan

The effect of incident light field ellipticity on the electromagnetically induced absorption (EIA) and electromagnetically induced transparency (EIT) resonances has been studied experimentally and computationally in Hanle configuration with longitudinal and transverse magnetic fields. We identify the Zeeman coherences that influence the resonance profile and study the role of coherence-transfer from excited to ground state via spontaneous emission as a function of ellipticity for the ${F}_{g}=2\ensuremath{\rightarrow}{F}_{e}=3$ transition of $^{87}\mathrm{Rb}$. The EIT resonance observed with the light field locked on the ${F}_{g}=1\ensuremath{\rightarrow}{F}_{e}=2$ transition of $^{87}\mathrm{Rb}$ is an influence of the nearby ${F}_{g}=1\ensuremath{\rightarrow}{F}_{e}=0$ closed and ${F}_{g}=1\ensuremath{\rightarrow}{F}_{e}=1$ open transitions. With increase in ellipticity the observed EIA and EIT resonances diminish in amplitude for a longitudinal magnetic field and are enhanced for a transverse magnetic field. We computationally account for these observations and discuss the factors that influence the EIA and EIT resonance amplitudes as a function of ellipticity and show that for a transverse field scan the ellipticity dependence of the EIA resonance amplitude can be accounted for without invoking the Doppler effect unlike for a longitudinal field scan. We also show that the maximum in the EIA resonance amplitude obtained for nonzero ellipticities with a longitudinal magnetic field depends on the closedness of the atomic system.

Physical Review A•Sep 16, 2010•23 citations

Sign reversal of Hanle electromagnetically induced absorption with orthogonal circularly polarized optical fields

Nibedita Ram, M. Pattabiraman

We study by computation and experiment an electromagnetically induced absorption resonance in the Hanle configuration with a transverse magnetic field on a closed F g → F e = F g +1 transition with co-propagating orthogonal circularly polarized probe and coupling optical fields. At high coupling field intensities, the Hanle resonance changes sign due to a shift in atomic population from Zeeman sublevels associated with a probe field cyclic transition to sublevels associated with a coupling field cyclic transition at zero magnetic field. We also show that a similar sign reversal does not occur for π-polarized and σ-polarized coupling fields.

Journal of Physics B Atomic Molecular and Optical Physics•Nov 29, 2010•17 citations

Effect of an additional magnetic field on Hanle-type absorption resonances

Raghwinder Singh Grewal, M. Pattabiraman

We computationally compare Hanle-type resonances for a transition of the line for magnetic field scans parallel (longitudinal scan) and perpendicular (transverse scan) to the direction of propagation of the optical field in the presence of an additional transverse magnetic field (TMF). For a linearly polarized light, the coherent population trapping (CPT) resonances split at line centre and are identical for both longitudinal and transverse scans. When the probe beam ellipticity is varied, the effect of the TMF is found to be opposite for longitudinal and transverse scans. For a longitudinal scan, the splitting observed in the CPT resonance evolves into an enhanced absorption resonance with an increase in ellipticity. For a transverse scan, the splitting vanishes at higher ellipticities. This can be understood in terms of population redistribution in the ground state sublevels and near-neighbor ground state coherences created by the TMF. We also show that the enhanced absorption signal that splits the CPT resonance strongly depends on transit time, and the CPT resonance strength depends on the excited state dephasing rate.

Journal of Physics B Atomic Molecular and Optical Physics•Sep 18, 2014•9 citations

Emergence of electromagnetically induced absorption in a perturbation solution of optical Bloch equations

Jelena Dimitrijević, D. Arsenović, B. M. Jelenkovic

We study phenomenon of electromagnetically induced absorption (EIA) in the Hanle configuration by applying a perturbative method to solve linear system of optical Bloch equations (OBEs) for the case of closed F g = 1 → F e = 2 transition. The method is applied assuming stationary case and a weak laser fields (Ω ≪ Γ, i.e., Rabi frequency small compared to spontaneous emission rate). This way, we calculate (both numerically and analytically) higher order corrections to density matrix. Odd corrections give contributions to optical coherences, while even corrections contribute to populations and Zeeman coherences. The method gives insight into mechanism of transfer of coherences and transfer of populations between Zeeman sublevels. We have found that the ground-state coherences (2nd correction to coherences) are crucial for the 4th correction to the change of populations which brings EIA type behavior of the Hanle spectrum. Using exact analytical expressions we further discuss further the role of decoherence of the ground-state sublevels when forming EIA.

Laser Physics•Apr 2, 2010•0 citations

Role of transverse magnetic fields in electromagnetically induced absorption for elliptically polarized light

Jelena Dimitrijević, Aleksandar J. Krmpot, Marina M. Mijailović +4 more

Using the closed ${F}_{g}\ensuremath{\rightarrow}{F}_{e}={F}_{g}+1$ $D2$ line transition of Rb atoms, we report experimental and numerical evidence of influence of additional transverse magnetic field when examining electromagnetically induced absorption (EIA) in the Hanle configuration. The effect was analyzed with two directions of additional magnetic field and in the cases of excitation with linear, elliptical, and circular laser light polarization. The transverse magnetic field brings substantial differences in the resonance line shape, amplitude, and width. Our theoretical model includes Doppler broadening. Numerical solutions of our theoretical model are in good agreement with experimental results. This analysis points out the importance of the presence of stray magnetic fields when studying EIA.

Physical Review A•Jan 16, 2008•28 citations

Perturbative Solution of Optical Bloch Equations for Analysis of Electromagnetically Induced Absorption

Jelena Dimitrijević, D. Arsenović, B. M. Jelenkovic

We study phenomenon of electromagnetically induced absorption in the Hanle configuration by solving time-dependent optical Bloch equations for the case of the closed multilevel F g = 1 → F e = 2 transition.Our model gives optical Bloch equations as a non-homogeneous system of ordinary linear differential equations.For weak laser fields (Ω Γ i.e.Rabi frequency small compared to spontaneous emission rate), a perturbative method to solve linear differential equations can be applied.Perturbative method is realized by solving (in the time-domain) higher-order corrections to the density matrix which in the sum converge to the exact solution of optical Bloch equations.By its form, each successive correction is also system of ordinary linear differential equations which depends on the solution of previous ones.Corrections are partitioned such that odd give corrections to optical coherences, while even give corrections to populations and Zeeman coherences.We present numerical results for the behavior of density matrix elements with successive corrections, and compare them with exact solution of optical Bloch equations.Electromagnetically induced absorption is observed as a 4th and higher (even) correction to populations, when behavior in respect to both time and magnetic field is viewed.Since in our method each correction depends on the solution of previous ones, we can analyze how (through mechanism of transfer of coherences and transfer of populations between Zeeman sublevels) electromagnetically induced absorption is formed.We also discuss qualitative differences in the behavior (with respect to time) of certain density matrix elements for magnetic fields "inside" and "outside" electromagnetically induced absorption resonance.

Acta Physica Polonica A•Oct 1, 2009•0 citations
The enhanced absorption Hanle effect has been studied for a closed transition Jg = 2 → Je = 3 with a transverse magnetic field in the presence of a coupling optical field. From an analysis of the individual probe and coupling field absorption profiles, it is shown that the Hanle electromagnetically induced absorption is governed by the transfer of Δm = ±2 and Δm = ±1 Zeeman coherences from the excited state to the ground state via spontaneous emission. The individual coherence contributions are governed by the intensity ratio of the optical fields. We show by computation and experiment that the magnetic field dependence of the forward scattered intensity can be used to distinguish the transfer of coherence contributions to the Hanle profile.
The effect of incident light field ellipticity on the electromagnetically induced absorption (EIA) and electromagnetically induced transparency (EIT) resonances has been studied experimentally and computationally in Hanle configuration with longitudinal and transverse magnetic fields. We identify the Zeeman coherences that influence the resonance profile and study the role of coherence-transfer from excited to ground state via spontaneous emission as a function of ellipticity for the ${F}_{g}=2\ensuremath{\rightarrow}{F}_{e}=3$ transition of 87Rb^{87}\mathrm{Rb}87Rb. The EIT resonance observed with the light field locked on the ${F}_{g}=1\ensuremath{\rightarrow}{F}_{e}=2$ transition of 87Rb^{87}\mathrm{Rb}87Rb is an influence of the nearby ${F}_{g}=1\ensuremath{\rightarrow}{F}_{e}=0$ closed and ${F}_{g}=1\ensuremath{\rightarrow}{F}_{e}=1$ open transitions. With increase in ellipticity the observed EIA and EIT resonances diminish in amplitude for a longitudinal magnetic field and are enhanced for a transverse magnetic field. We computationally account for these observations and discuss the factors that influence the EIA and EIT resonance amplitudes as a function of ellipticity and show that for a transverse field scan the ellipticity dependence of the EIA resonance amplitude can be accounted for without invoking the Doppler effect unlike for a longitudinal field scan. We also show that the maximum in the EIA resonance amplitude obtained for nonzero ellipticities with a longitudinal magnetic field depends on the closedness of the atomic system.
We study by computation and experiment an electromagnetically induced absorption resonance in the Hanle configuration with a transverse magnetic field on a closed F g → F e = F g +1 transition with co-propagating orthogonal circularly polarized probe and coupling optical fields. At high coupling field intensities, the Hanle resonance changes sign due to a shift in atomic population from Zeeman sublevels associated with a probe field cyclic transition to sublevels associated with a coupling field cyclic transition at zero magnetic field. We also show that a similar sign reversal does not occur for π-polarized and σ-polarized coupling fields.
We computationally compare Hanle-type resonances for a transition of the line for magnetic field scans parallel (longitudinal scan) and perpendicular (transverse scan) to the direction of propagation of the optical field in the presence of an additional transverse magnetic field (TMF). For a linearly polarized light, the coherent population trapping (CPT) resonances split at line centre and are identical for both longitudinal and transverse scans. When the probe beam ellipticity is varied, the effect of the TMF is found to be opposite for longitudinal and transverse scans. For a longitudinal scan, the splitting observed in the CPT resonance evolves into an enhanced absorption resonance with an increase in ellipticity. For a transverse scan, the splitting vanishes at higher ellipticities. This can be understood in terms of population redistribution in the ground state sublevels and near-neighbor ground state coherences created by the TMF. We also show that the enhanced absorption signal that splits the CPT resonance strongly depends on transit time, and the CPT resonance strength depends on the excited state dephasing rate.
We study phenomenon of electromagnetically induced absorption (EIA) in the Hanle configuration by applying a perturbative method to solve linear system of optical Bloch equations (OBEs) for the case of closed F g = 1 → F e = 2 transition. The method is applied assuming stationary case and a weak laser fields (Ω ≪ Γ, i.e., Rabi frequency small compared to spontaneous emission rate). This way, we calculate (both numerically and analytically) higher order corrections to density matrix. Odd corrections give contributions to optical coherences, while even corrections contribute to populations and Zeeman coherences. The method gives insight into mechanism of transfer of coherences and transfer of populations between Zeeman sublevels. We have found that the ground-state coherences (2nd correction to coherences) are crucial for the 4th correction to the change of populations which brings EIA type behavior of the Hanle spectrum. Using exact analytical expressions we further discuss further the role of decoherence of the ground-state sublevels when forming EIA.
Using the closed ${F}_{g}\ensuremath{\rightarrow}{F}_{e}={F}_{g}+1$ D2D2D2 line transition of Rb atoms, we report experimental and numerical evidence of influence of additional transverse magnetic field when examining electromagnetically induced absorption (EIA) in the Hanle configuration. The effect was analyzed with two directions of additional magnetic field and in the cases of excitation with linear, elliptical, and circular laser light polarization. The transverse magnetic field brings substantial differences in the resonance line shape, amplitude, and width. Our theoretical model includes Doppler broadening. Numerical solutions of our theoretical model are in good agreement with experimental results. This analysis points out the importance of the presence of stray magnetic fields when studying EIA.
We study phenomenon of electromagnetically induced absorption in the Hanle configuration by solving time-dependent optical Bloch equations for the case of the closed multilevel F g = 1 → F e = 2 transition.Our model gives optical Bloch equations as a non-homogeneous system of ordinary linear differential equations.For weak laser fields (Ω Γ i.e.Rabi frequency small compared to spontaneous emission rate), a perturbative method to solve linear differential equations can be applied.Perturbative method is realized by solving (in the time-domain) higher-order corrections to the density matrix which in the sum converge to the exact solution of optical Bloch equations.By its form, each successive correction is also system of ordinary linear differential equations which depends on the solution of previous ones.Corrections are partitioned such that odd give corrections to optical coherences, while even give corrections to populations and Zeeman coherences.We present numerical results for the behavior of density matrix elements with successive corrections, and compare them with exact solution of optical Bloch equations.Electromagnetically induced absorption is observed as a 4th and higher (even) correction to populations, when behavior in respect to both time and magnetic field is viewed.Since in our method each correction depends on the solution of previous ones, we can analyze how (through mechanism of transfer of coherences and transfer of populations between Zeeman sublevels) electromagnetically induced absorption is formed.We also discuss qualitative differences in the behavior (with respect to time) of certain density matrix elements for magnetic fields "inside" and "outside" electromagnetically induced absorption resonance.