arXiv:quant-ph/0006096 · Physical Review A

Efficient Raman sideband generation in a coherent atomic medium

Arno Huss, Norbert Peer, Roland Lammegger, Eugeny Korsunsky, Laurentius Windholz

Published Dec 4, 2000• 29 citations

Abstract

We demonstrate the efficient generation of Raman sidebands in a medium coherently prepared in a dark state by continuous-wave low-intensity laser radiation. Our experiment is performed in sodium vapor excited in $\ensuremath{\Lambda}$ configuration on the ${D}_{1}$ line by two laser fields of resonant frequencies ${\ensuremath{\omega}}_{1}$ and ${\ensuremath{\omega}}_{2},$ and probed by a third field ${\ensuremath{\omega}}_{3}.$ First-order sidebands for frequencies ${\ensuremath{\omega}}_{1},$ ${\ensuremath{\omega}}_{2}$ and up to the third-order sidebands for frequency ${\ensuremath{\omega}}_{3}$ are observed. The generation starts at a power as low as 10 \ensuremath{\mu}W for each input field. Dependences of the intensities of both input and generated waves on the frequency difference $({\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}),$ on the frequency ${\ensuremath{\omega}}_{3},$ and on the optical density are investigated.

DOI: 10.1103/physreva.63.013802

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arXiv:quant-ph/0006096 · Physical Review A

Efficient Raman sideband generation in a coherent atomic medium

Arno Huss, Norbert Peer, Roland Lammegger, Eugeny Korsunsky, Laurentius Windholz

Published Dec 4, 2000• 29 citations

arXiv HTML PDF

Abstract

\ensuremath{\Lambda}

configuration on the

{D}_{1}

line by two laser fields of resonant frequencies

{\ensuremath{\omega}}_{1}

and

{\ensuremath{\omega}}_{2},

and probed by a third field

{\ensuremath{\omega}}_{3}.

First-order sidebands for frequencies

{\ensuremath{\omega}}_{1},

{\ensuremath{\omega}}_{2}

and up to the third-order sidebands for frequency

{\ensuremath{\omega}}_{3}

are observed. The generation starts at a power as low as 10 \ensuremath{\mu}W for each input field. Dependences of the intensities of both input and generated waves on the frequency difference

({\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}),

on the frequency

{\ensuremath{\omega}}_{3},

and on the optical density are investigated.

DOI: 10.1103/physreva.63.013802

Related papers

Generation of subfemtosecond pulse by nonadiabatic Raman excitation

Jian Wu, Kun Wu, Heping Zeng

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Stimulated Raman Scattering in Vapor-Deposited Solid Hydrogen Film

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Generation of frequency correlated laser beams is of importance in various applications, in particular, for extending the frequency of the laser Raman microwave clock1 into the millimeter region where acoustooptic methods are not available. We propose and demonstrate an all-optical technique for such a purpose. The technique is based on the recently observed Raman-shifted oscillation2 that occurs when a three-level atomic system of Λ type is optically pumped and placed in a ring cavity. Our initial experiments are performed in sodium vapor pumped by a cw ring dye laser. Raman-shifted oscillation, detuned from the pump laser by 1.772 GHz which is the ground state hyperfine splitting of sodium, occurs in the wings of the Doppler broadened D1 line. This Raman-shifted oscillation is demonstrated to be highly frequency correlated with the pumping laser when the two are heterodyned on a fast photodetector. In our experiments the heterodyne beat signal at 1.772 GHz had a linewidth as low as 17 kHz, whereas the pumping laser has a rms frequency fluctuation of 300 kHz. The beat signal stays narrowband when the pumping laser is unlocked from the reference cavity increasing its rms frequency fluctation to ~10MHz.Generation of frequency correlated laser beams is of importance in various applications, in particular, for extending the frequency of the laser Raman microwave clock1 into the millimeter region where acoustooptic methods are not available. We propose and demonstrate an all-optical technique for such a purpose. The technique is based on the recently observed Raman-shifted oscillation2 that occurs when a three-level atomic system of Λ type is optically pumped and placed in a ring cavity. Our initial experiments are performed in sodium vapor pumped by a cw ring dye laser. Raman-shifted oscillation, detuned from the pump laser by 1.772 GHz which is the ground state hyperfine splitting of sodium, occurs in the wings of the Doppler broadened D1 line. This Raman-shifted oscillation is demonstrated to be highly frequency correlated with the pumping laser when the two are heterodyned on a fast photodetector. In our experiments the heterodyne beat signal at 1.772 GHz had a linewidth as low as 17 kHz, whereas the pumping laser has a rms frequency fluctuation of 300 kHz. The beat signal stays narrowband when the pumping laser is unlocked from the reference cavity increasing its rms frequency fluctation to ~10MHz.

Annual Meeting Optical Society of AmericaJan 1, 19850 citations

Continuous-wave second-harmonic generation in sodium vapor

Bruce Sinclair, Malcolm H. Dunn

A high-resolution study of magnetic-field-induced second-harmonic generation in sodium vapor has been carried out with use of a single-frequency continuous-wave dye laser. Resonant enhancement was obtained by tuning the laser to the frequency of the 3S\ensuremath{\rightarrow}4D two-photon transition of the sodium atom. Experimental and theoretical results are presented showing the variation of the power and polarization properties of the second-harmonic radiation as the laser is tuned across the two-photon resonance, and as the transverse magnetic field is varied.A high-resolution study of magnetic-field-induced second-harmonic generation in sodium vapor has been carried out with use of a single-frequency continuous-wave dye laser. Resonant enhancement was obtained by tuning the laser to the frequency of the 3S\ensuremath{\rightarrow}4D two-photon transition of the sodium atom. Experimental and theoretical results are presented showing the variation of the power and polarization properties of the second-harmonic radiation as the laser is tuned across the two-photon resonance, and as the transverse magnetic field is varied.

Physical Review ANov 1, 19869 citations

\ensuremath{\Lambda}

configuration on the

{D}_{1}

line by two laser fields of resonant frequencies

{\ensuremath{\omega}}_{1}

and

{\ensuremath{\omega}}_{2},

and probed by a third field

{\ensuremath{\omega}}_{3}.

First-order sidebands for frequencies

{\ensuremath{\omega}}_{1},

{\ensuremath{\omega}}_{2}

and up to the third-order sidebands for frequency

{\ensuremath{\omega}}_{3}

are observed. The generation starts at a power as low as 10 \ensuremath{\mu}W for each input field. Dependences of the intensities of both input and generated waves on the frequency difference

({\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2}),

on the frequency

{\ensuremath{\omega}}_{3},

and on the optical density are investigated.

{}^{10}

W cm${}^{\ensuremath{-}2}$ probe beam creates a maximum sideband shift of >90 meV from the carrier frequency, resulting in an effective bandwidth of 200 meV. The sidebands can be tuned and controlled by the intensity and temporal profile of the probe pulse. The fact that the coherence is observed in a microplasma demonstrates that Rabi cycling is possible at high temperature with moderately high laser intensities as long as transitions close to the driving frequency ($\ensuremath{\Delta}$\ensuremath{\sim}2% ${\ensuremath{\omega}}_{c}$) are available. Plasma excitation combined with Rabi-shifting measurements also serves as a means to simultaneously extract quantitative ratios for the transition-dipole moments between multiple sets of highly excited states with transitions in the optical regime.