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

Conference on Lasers and Electro-Optics

Comparative study of index of refraction: The strongly driven and the degenerate two-level systems

R.-H. Rinkleff, L. Spani Molella, A. Rocco, Andreas Wicht, K. Danzmann

Published May 1, 2008• 0 citations
Publisher

Abstract

This study compares the experimental results of absorption and refractive index of a probe laser measured in a strongly driven two-level atom with the results measured in a degenerate two-level system using pump-probe spectroscopy. This work demonstrates the possibility of realization an anomalous dispersive transparent medium using the strongly driven 4s21S0- 4s4p1P1Ca transition. Absorption and phase shift profiles are measured as function of the driving field intensity using a Ca atomic beam. With increasing driving field intensities absorption and phase shift decrease, but the absorption decreases stronger than the dispersion. Results show that the resonant absorption and the anomalous dispersion are reduced with respect to the non-driving case by a factor 490 and 47, respectively. This means that a ~ 10-fold enhancement of the amount of dispersion provided per amount of absorption is attained.

DOI
10.1109/cleo.2008.4551981

Related papers

Anomalous dispersion of transparent atomic two- and three-level ensembles

Alessandra S. Rocco, Andreas Wicht, R.-H. Rinkleff +1 more

The absorption and dispersion properties of a driven two-level atomic system probed by a weak field have been measured simultaneously with a phase modulated Mach-Zehnder interferometer. We find that the resonant absorption and the negative dispersion are reduced with respect to the nondriving case by a factor of 490 and 47, respectively, which is in good agreement with the theory. This means a $\ensuremath{\sim}10$-fold enhancement of the amount of dispersion provided per amount of residual absorption. The experimental values are compared to the requirements that have to be fulfilled for the realization of a broadband, high finesse optical cavity. Finally, we propose a specific degenerate three-level system that overcomes some of the shortcomings of the driven two-level atom.

Physical Review A•Nov 11, 2002•32 citations

Negative dispersion without absorption in atomic ensembles

Rocco, Alessandra

Dott. Alessandra Rocco Negative dispersion without absorption in atomic ensembles In this work the optical properties of a calcium atomic beam, strongly driven on the transition, are investigated, in order to obtain a coherently prepared medium with the right amount of negative dispersion at a point of zero absorption. From the theory it is well known that a strongly driven Two-Level system exhibits such properties. Such a medium could in particular be used to fill an optical resonator in order to obtain a broadband high finesse cavity (White Light Cavity). For the investigations a spectroscopic method had been used, consisting of a Mach-Zehnder interferometer with a phase modulated arm. In this way it is possible to perform a high sensitive simultaneous measurement of both phase shift and absorption profiles in a calcium atomic beam, for an increasing driving field, which frequency is stabilized on the transition 4s2 S0 4s4p P1 at 423nm. For the first time both absorption and phase shift were systematic investigated as function of the driving field intensity, while it was developed a new geometrical configuration for the atomic oven which permitted to reach a higher particle density in the interaction zone. It was then possible to calculate the values of derivative of phase shift and absorption at the transition frequency, where the dispersion results anomalous, having fitted the measured curves to the phase shift and absorption profiles for a strongly driven Two-Level Atom. An analysis of the evolution of the both the quantities as driving field function could be then performed. The theoretical analysis of the strongly driven two level system could then be experimentally verified, especially that the absorption decreases stronger than dispersion with an increasing driving field. It was in fact measured a decreasing of a factor 53 in the dispersion, between the not driven and driven atomic system while the corresponding absorption decreased of a factor 330, for a value of the driving field of D 2π54.4MHz. The possibility of inserting the medium inside an optical resonator to obtain a broadband high finesse cavity has also been discussed. The data analysis showed that even if the λ compensation was reachable in the achieved condition, the residual absorption was still too high to realize a White Light Cavity. The configuration for further development of the system which should allow this realization was also analyzed, together with a comparison with the performances of different atomic systems.

•Jan 1, 2001•1 citation

Negative dispersion without absorption

A. Rocco, Andreas Wicht, M. Muller +2 more

Summary form only given. We study the optical properties of negative dispersive but nevertheless transparent media. Such medium can be generated using atomic phase coherence. Theoretical studies have shown that strongly driven two level systems may exhibit the desired optical properties, that is negative dispersion of a well defined amount at a point of vanishing absorption. When this medium is placed inside an optical resonator the linewidth is increased without sacrificing its build up. We present the experimental setup which is used to realize a negative dispersive non-absorbing medium. To obtain a strongly driven two level system a calcium atomic beam is pumped at the transition 4s/sup 21/S/sub 0//spl rarr/4s4p/sup 1/P/sub 1/. The optical properties of the beam are studied.

Quantum Electronics and Laser Science Conference•Jan 20, 2003•0 citations

Comparative study of anomalous dispersive transparent media

Andreas Wicht, R.-H. Rinkleff, L. Spani Molella +1 more

We present a comparative theoretical analysis of five different atomic schemes with respect to their performance as negative (anomalous) dispersive transparent media. The schemes discussed are the strongly driven and the degenerate two-level system, two closely spaced gain lines, and two slightly different double-$\ensuremath{\Lambda}$ schemes with incoherent pumping. The analysis shows that the degenerate two-level scheme is best suited for applications for which only modest negative dispersion but strongly reduced absorption is required, and dissipation and loss of the optical fields have to be avoided. Two closely spaced gain lines and one of the double-$\ensuremath{\Lambda}$ schemes are the best choice for applications which rely on large negative dispersion, but are not too sensitive to residual absorption and dissipation.

Physical Review A•Dec 31, 2002•17 citations

Enhancing the index of refraction under convenient conditions

Carsten Szymanowski, Christoph H. Keitel

We investigate the possibility of increasing the achievable index of refraction and the slope of the dispersion while simultaneously minimizing absorption in a driven two-level system. The analysis is performed non-linearly in both the probing laser field and Doppler and collision broadening have been incorporated for the sake of a realistic treatment. We compare the achievable index of refraction without absorption quantitatively with known results of several favorable three- and four-level systems, find our system less sensitive to Doppler broadening in a collinear set-up of both fields and apply our considerations to the particular example of caesium.

Journal of Physics B Atomic Molecular and Optical Physics•Dec 14, 1994•33 citations

Experimental investigations of the absorption and dispersion profiles of a strongly driven transition: Two-level system with a weak probe

Changjiang Wei, Neil B. Manson

The paper reports on experimental investigations of absorption and dispersion profiles of a strongly driven hyperfine transition at various pump field intensities and detunings when probed by a weak field. The transition lies at 5.4 MHz and corresponds to the ${\mathit{I}}_{\mathit{z}}$=0\ensuremath{\leftrightarrows}-1 nuclear magnetic transition within the electron spin singlet of the $^{3}$A ground state of the nitrogen-vacancy (NV) center in diamond. The inhomogeneous linewidth of the transition is 8 kHz whereas the homogeneous linewidth is 2.7 kHz, which is a factor of 3 larger than that limited by the population relaxations. The absorption and dispersion are obtained using Raman heterodyne detection, a coherent optically detected magnetic-resonance technique. Measurements are performed in a situation where there is an anticrossing of the ground-state electron-spin levels, as this leads to an enhancement of the hyperfine transition strengths and the optical sensitivity. Weak probe fields with Rabi frequency 0.6 kHz could then be used. The absorption and dispersion profiles were recorded for on-resonance pump fields of various strengths with Rabi frequencies of 0, 2.1, 3.7, 6.6, 11.8, and 21 kHz. In addition, the responses were recorded for an off-resonance field with a Rabi frequency of 55 kHz and detunings between -40 and +40 kHz. The corresponding response of an idealized driven two-level system has been calculated using an established density-matrix equation of motion formalism.When normalized to the profiles with no driving field, the calculated and experimental profiles are in excellent agreement. The nitrogen-vacancy system provides a very clear experimental illustration of a driven two-level system and some aspects are highlighted. For on-resonance pumping, the dispersion profile consists of a positive and a negative absorptionlike peak separated by twice the pump Rabi frequency. The peaks correspond to a significant signal strength (index of refraction) whereas at the frequency of the peaks in dispersion, the absorption is zero. The corresponding absorption profile consists of two dispersionlike features separated by twice the pump Rabi frequency, and between the two features there is negative absorption or gain. For off-resonance pumping, there are again two features. For example, in absorption response, there is an absorption peak and an amplification peak symmetrically displaced from the pump frequency by the generalized Rabi frequency. In this off-resonance pumping situation, it is pointed out that gain occurs where there is inversion in the dressed state whereas gain for the on-resonance pumping situation is achieved without population inversion in either the bare or dressed state.

Physical Review A•Jun 1, 1994•39 citations
This study compares the experimental results of absorption and refractive index of a probe laser measured in a strongly driven two-level atom with the results measured in a degenerate two-level system using pump-probe spectroscopy. This work demonstrates the possibility of realization an anomalous dispersive transparent medium using the strongly driven 4s21S0- 4s4p1P1Ca transition. Absorption and phase shift profiles are measured as function of the driving field intensity using a Ca atomic beam. With increasing driving field intensities absorption and phase shift decrease, but the absorption decreases stronger than the dispersion. Results show that the resonant absorption and the anomalous dispersion are reduced with respect to the non-driving case by a factor 490 and 47, respectively. This means that a ~ 10-fold enhancement of the amount of dispersion provided per amount of absorption is attained.
The absorption and dispersion properties of a driven two-level atomic system probed by a weak field have been measured simultaneously with a phase modulated Mach-Zehnder interferometer. We find that the resonant absorption and the negative dispersion are reduced with respect to the nondriving case by a factor of 490 and 47, respectively, which is in good agreement with the theory. This means a $\ensuremath{\sim}10$-fold enhancement of the amount of dispersion provided per amount of residual absorption. The experimental values are compared to the requirements that have to be fulfilled for the realization of a broadband, high finesse optical cavity. Finally, we propose a specific degenerate three-level system that overcomes some of the shortcomings of the driven two-level atom.
Dott. Alessandra Rocco Negative dispersion without absorption in atomic ensembles In this work the optical properties of a calcium atomic beam, strongly driven on the transition, are investigated, in order to obtain a coherently prepared medium with the right amount of negative dispersion at a point of zero absorption. From the theory it is well known that a strongly driven Two-Level system exhibits such properties. Such a medium could in particular be used to fill an optical resonator in order to obtain a broadband high finesse cavity (White Light Cavity). For the investigations a spectroscopic method had been used, consisting of a Mach-Zehnder interferometer with a phase modulated arm. In this way it is possible to perform a high sensitive simultaneous measurement of both phase shift and absorption profiles in a calcium atomic beam, for an increasing driving field, which frequency is stabilized on the transition 4s2 S0 4s4p P1 at 423nm. For the first time both absorption and phase shift were systematic investigated as function of the driving field intensity, while it was developed a new geometrical configuration for the atomic oven which permitted to reach a higher particle density in the interaction zone. It was then possible to calculate the values of derivative of phase shift and absorption at the transition frequency, where the dispersion results anomalous, having fitted the measured curves to the phase shift and absorption profiles for a strongly driven Two-Level Atom. An analysis of the evolution of the both the quantities as driving field function could be then performed. The theoretical analysis of the strongly driven two level system could then be experimentally verified, especially that the absorption decreases stronger than dispersion with an increasing driving field. It was in fact measured a decreasing of a factor 53 in the dispersion, between the not driven and driven atomic system while the corresponding absorption decreased of a factor 330, for a value of the driving field of D 2π54.4MHz. The possibility of inserting the medium inside an optical resonator to obtain a broadband high finesse cavity has also been discussed. The data analysis showed that even if the λ compensation was reachable in the achieved condition, the residual absorption was still too high to realize a White Light Cavity. The configuration for further development of the system which should allow this realization was also analyzed, together with a comparison with the performances of different atomic systems.
Summary form only given. We study the optical properties of negative dispersive but nevertheless transparent media. Such medium can be generated using atomic phase coherence. Theoretical studies have shown that strongly driven two level systems may exhibit the desired optical properties, that is negative dispersion of a well defined amount at a point of vanishing absorption. When this medium is placed inside an optical resonator the linewidth is increased without sacrificing its build up. We present the experimental setup which is used to realize a negative dispersive non-absorbing medium. To obtain a strongly driven two level system a calcium atomic beam is pumped at the transition 4s/sup 21/S/sub 0//spl rarr/4s4p/sup 1/P/sub 1/. The optical properties of the beam are studied.
We present a comparative theoretical analysis of five different atomic schemes with respect to their performance as negative (anomalous) dispersive transparent media. The schemes discussed are the strongly driven and the degenerate two-level system, two closely spaced gain lines, and two slightly different double-$\ensuremath{\Lambda}$ schemes with incoherent pumping. The analysis shows that the degenerate two-level scheme is best suited for applications for which only modest negative dispersion but strongly reduced absorption is required, and dissipation and loss of the optical fields have to be avoided. Two closely spaced gain lines and one of the double-$\ensuremath{\Lambda}$ schemes are the best choice for applications which rely on large negative dispersion, but are not too sensitive to residual absorption and dissipation.
We investigate the possibility of increasing the achievable index of refraction and the slope of the dispersion while simultaneously minimizing absorption in a driven two-level system. The analysis is performed non-linearly in both the probing laser field and Doppler and collision broadening have been incorporated for the sake of a realistic treatment. We compare the achievable index of refraction without absorption quantitatively with known results of several favorable three- and four-level systems, find our system less sensitive to Doppler broadening in a collinear set-up of both fields and apply our considerations to the particular example of caesium.
The paper reports on experimental investigations of absorption and dispersion profiles of a strongly driven hyperfine transition at various pump field intensities and detunings when probed by a weak field. The transition lies at 5.4 MHz and corresponds to the Iz{\mathit{I}}_{\mathit{z}}Iz​=0\ensuremath{\leftrightarrows}-1 nuclear magnetic transition within the electron spin singlet of the 3^{3}3A ground state of the nitrogen-vacancy (NV) center in diamond. The inhomogeneous linewidth of the transition is 8 kHz whereas the homogeneous linewidth is 2.7 kHz, which is a factor of 3 larger than that limited by the population relaxations. The absorption and dispersion are obtained using Raman heterodyne detection, a coherent optically detected magnetic-resonance technique. Measurements are performed in a situation where there is an anticrossing of the ground-state electron-spin levels, as this leads to an enhancement of the hyperfine transition strengths and the optical sensitivity. Weak probe fields with Rabi frequency 0.6 kHz could then be used. The absorption and dispersion profiles were recorded for on-resonance pump fields of various strengths with Rabi frequencies of 0, 2.1, 3.7, 6.6, 11.8, and 21 kHz. In addition, the responses were recorded for an off-resonance field with a Rabi frequency of 55 kHz and detunings between -40 and +40 kHz. The corresponding response of an idealized driven two-level system has been calculated using an established density-matrix equation of motion formalism.When normalized to the profiles with no driving field, the calculated and experimental profiles are in excellent agreement. The nitrogen-vacancy system provides a very clear experimental illustration of a driven two-level system and some aspects are highlighted. For on-resonance pumping, the dispersion profile consists of a positive and a negative absorptionlike peak separated by twice the pump Rabi frequency. The peaks correspond to a significant signal strength (index of refraction) whereas at the frequency of the peaks in dispersion, the absorption is zero. The corresponding absorption profile consists of two dispersionlike features separated by twice the pump Rabi frequency, and between the two features there is negative absorption or gain. For off-resonance pumping, there are again two features. For example, in absorption response, there is an absorption peak and an amplification peak symmetrically displaced from the pump frequency by the generalized Rabi frequency. In this off-resonance pumping situation, it is pointed out that gain occurs where there is inversion in the dressed state whereas gain for the on-resonance pumping situation is achieved without population inversion in either the bare or dressed state.