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 Pacific Rim (CLEO-PR)

Coherence control in a fs-dephasing medium by means of differential phase pumping of ultra-broadband pulses

H. Nishioka, H. Koutaka, Kenji Ueda

Published Nov 13, 2002• 0 citations
Publisher

Abstract

The coherent couplings and decoupling in multi-level and ultra-broadband materials (T/sub 2/<10 fs) have been demonstrated by means of differential phase pumping of intense and ultra-broadband pulses. Absorption suppression and gain enhancement was observed as a function of differential-Fourier phase of the intense ultra-broadband excitations.

DOI
10.1109/cleopr.2001.971126

Related papers

Quantum interference in a fs-dephasing medium induced by an intense hyper-continuum

H. Nishioka, H. Koutaka, Kenji Ueda

Summary form only given. We have demonstrated absorption enhancement and emission suppression by the coherence control in the fs-dephasing medium. The ultra-broadband differential phase excitation controls the coupling between multiple energy levels. The pumping scheme is possibly applied to further broadband materials for the control of general material properties unlimited within the optical characteristics. Especially, coherence control by the UV and VUV broadband excitations coupling to the same continuum drastically changes ionization and reaction properties of material. Applications for reaction control, material processing, or optical control of short wavelength system, that are essentially connecting with their short-live and ultra-broadband nature may be remarkable future of this scheme.

Conference on Lasers and Electro-Optics•Jan 1, 2001•0 citations

Quantum interference effects in a femtosecond-dephasing medium

H. Nishioka, H. Koutaka, Ken-ichi Ueda

Coherence control in a _ -type three-level system having an ultrafast (<10 fs) dephasing time has been demonstrated. Coherences in the multilevel system were excited by an intense supercontinuum yielding terahertz Rabi frequencies. The coherence was controlled by changing the interaction phase between the excited coherences and the broadband light field in the double-pulse pumping scheme.

Optics Express•May 21, 2001•2 citations

Phase Control of Medium Gain in a Double Two-Level System: From Ultrashort to Long Pulse Regime

F. A. Hashmi, M. A. Bouchène

We consider a double two-level system in which each single two-level system is driven by a strong pulse. The light shifts induced by the strong field are probed by a weak pulse that connects the two sub-system in a crossed manner connecting the ground state of one system with the excited state of the other and vice versa. We are interested in coherent control of medium gain for the weak pulse and we demonstrate the conditions on laser and atomic parameters that render this control possible. Both ultra-short and long pulse regimes are discussed

•Sep 1, 2007•0 citations

Subfemtosecond pulse generation by cascade-stimulated Raman scattering with modulated Raman excitation

Kun Wu, Jian Wu, Heping Zeng

Subfemtosecond (sub-fs) pulses can be generated by cascade-stimulated Raman scattering in a Raman medium with modulated Raman excitations, driven by two sufficiently intense laser beams, one of which is amplitude modulated. The nonadiabatic Raman interaction establishes a strong modulated Raman coherence, which supports compression of the generated broadband Raman sidebands to a train of sub-fs pulses regardless of whether the carrier frequencies of the driving lasers are tuned above, below or on two-photon Raman resonance.

Journal of Physics B Atomic Molecular and Optical Physics•Oct 8, 2003•3 citations

Coherent Transient Enhancement of Optically Induced Resonant Transitions

Nirit Dudovich, Dan Oron, Yaron R. Silberberg

By applying pulse shaping techniques to a broadband 100 fs pulse in resonance with a two-level atomic transition, we are able to enhance the peak transient excited level population relative to that achievable with transform limited pulses. We also demonstrate how the dispersion induced by the absorption line itself leads to similar rapidly oscillating transients in the excited population. These transient population effects are applicable in any multiphoton resonant transition.

Physical Review Letters•Mar 7, 2002•102 citations

Quantum control of optical four-wave mixing with femtosecond !-3! laser pulses: coherent ac Stark nonlinear spectroscopy

Carles Serrat

The four-wave mixing produced with two ultrashort phase-locked !-3! laser pulses propagating coherently in a two-level system in the infrared spectral region is shown to depend on the pulses relative phase. The Maxwell-Bloch equations are solved beyond the rotating-wave approximation to account for field frequencies which are largely detuned from the atomic resonance. The relative phase dominating the efficiency of the coupling to the 5! anti-Stokes Raman component is determined by sign of the total ac Stark shift induced in the system, in such a way that the phase influence disappears precisely where the ac Stark effect due to both pulses is compensated. This fundamental quantum interference effect can be the basis for nonlinear ultrafast optical spectroscopy techniques. Phenomena arising from the coherent control of nonlinear interactions are of importance in fields as diverse as optoelectronics and materials research, in high harmonic generation, in photoionization or molecular dissociation, and in biological applications such as spectroscopy and imaging, among others [1, 2, 3, 4, 5, 6, 7]. Optical quantum coherent control is based on the fact that the phases of interfering transition amplitudes in light-matter interactions can be controlled through the optical phase of coherent light sources that drive the interaction, in such a way that the transition rates to final states and the dynamics at various stages of the process can be modified [1]. In a recent paper [8], a theoretical investigation on the quantum coherent control of the optical transient four-wave mixing of two intense phase-locked femtosecond laser pulses of central angular frequencies ω and 3ω propagating in a two-level atom (TLA) was reported. It was shown how the nonlinear (χ (3) ) coupling to the antiStokes Raman field at frequency 5ω depends critically on the initial relative phase φ of the propagating pulses. In Ref. [8], the study was centered to intense pulses in the visible and ultraviolet spectral regions, with frequencies at resonance or lower than the atomic transition. The phenomena observed in [8], however, can be scaled to various laser and material parameters. In the infrared spectral range, for instance, experiments on ultrafast molecular dynamics are frequently performed by help of twocolor pump probe nonlinear spectroscopy techniques. In this type of studies, due to the high intensities inherent to ultrashort (subpicosecond) pulses, nonlinear effects such as stimulated Raman processes may become important and are often utilized as a complementary tool to gain information [9]. In this Letter, we address the conditions for quantum coherent control of transient four-wave mixing interactions with two phase-locked ω-3ω femtosecond laser pulses in the mid-IR spectral region. Our purpose is to reveal the basic physics for a strict two-level medium and to this end the Maxwell-Bloch TLA will be considered. We will study pulses with a duration of 300 fs (with a w 5w

•Jan 1, 2008•0 citations
The coherent couplings and decoupling in multi-level and ultra-broadband materials (T/sub 2/<10 fs) have been demonstrated by means of differential phase pumping of intense and ultra-broadband pulses. Absorption suppression and gain enhancement was observed as a function of differential-Fourier phase of the intense ultra-broadband excitations.
Summary form only given. We have demonstrated absorption enhancement and emission suppression by the coherence control in the fs-dephasing medium. The ultra-broadband differential phase excitation controls the coupling between multiple energy levels. The pumping scheme is possibly applied to further broadband materials for the control of general material properties unlimited within the optical characteristics. Especially, coherence control by the UV and VUV broadband excitations coupling to the same continuum drastically changes ionization and reaction properties of material. Applications for reaction control, material processing, or optical control of short wavelength system, that are essentially connecting with their short-live and ultra-broadband nature may be remarkable future of this scheme.
We consider a double two-level system in which each single two-level system is driven by a strong pulse. The light shifts induced by the strong field are probed by a weak pulse that connects the two sub-system in a crossed manner connecting the ground state of one system with the excited state of the other and vice versa. We are interested in coherent control of medium gain for the weak pulse and we demonstrate the conditions on laser and atomic parameters that render this control possible. Both ultra-short and long pulse regimes are discussed
Subfemtosecond (sub-fs) pulses can be generated by cascade-stimulated Raman scattering in a Raman medium with modulated Raman excitations, driven by two sufficiently intense laser beams, one of which is amplitude modulated. The nonadiabatic Raman interaction establishes a strong modulated Raman coherence, which supports compression of the generated broadband Raman sidebands to a train of sub-fs pulses regardless of whether the carrier frequencies of the driving lasers are tuned above, below or on two-photon Raman resonance.
The four-wave mixing produced with two ultrashort phase-locked !-3! laser pulses propagating coherently in a two-level system in the infrared spectral region is shown to depend on the pulses relative phase. The Maxwell-Bloch equations are solved beyond the rotating-wave approximation to account for field frequencies which are largely detuned from the atomic resonance. The relative phase dominating the efficiency of the coupling to the 5! anti-Stokes Raman component is determined by sign of the total ac Stark shift induced in the system, in such a way that the phase influence disappears precisely where the ac Stark effect due to both pulses is compensated. This fundamental quantum interference effect can be the basis for nonlinear ultrafast optical spectroscopy techniques. Phenomena arising from the coherent control of nonlinear interactions are of importance in fields as diverse as optoelectronics and materials research, in high harmonic generation, in photoionization or molecular dissociation, and in biological applications such as spectroscopy and imaging, among others [1, 2, 3, 4, 5, 6, 7]. Optical quantum coherent control is based on the fact that the phases of interfering transition amplitudes in light-matter interactions can be controlled through the optical phase of coherent light sources that drive the interaction, in such a way that the transition rates to final states and the dynamics at various stages of the process can be modified [1]. In a recent paper [8], a theoretical investigation on the quantum coherent control of the optical transient four-wave mixing of two intense phase-locked femtosecond laser pulses of central angular frequencies ω and 3ω propagating in a two-level atom (TLA) was reported. It was shown how the nonlinear (χ (3) ) coupling to the antiStokes Raman field at frequency 5ω depends critically on the initial relative phase φ of the propagating pulses. In Ref. [8], the study was centered to intense pulses in the visible and ultraviolet spectral regions, with frequencies at resonance or lower than the atomic transition. The phenomena observed in [8], however, can be scaled to various laser and material parameters. In the infrared spectral range, for instance, experiments on ultrafast molecular dynamics are frequently performed by help of twocolor pump probe nonlinear spectroscopy techniques. In this type of studies, due to the high intensities inherent to ultrashort (subpicosecond) pulses, nonlinear effects such as stimulated Raman processes may become important and are often utilized as a complementary tool to gain information [9]. In this Letter, we address the conditions for quantum coherent control of transient four-wave mixing interactions with two phase-locked ω-3ω femtosecond laser pulses in the mid-IR spectral region. Our purpose is to reveal the basic physics for a strict two-level medium and to this end the Maxwell-Bloch TLA will be considered. We will study pulses with a duration of 300 fs (with a w 5w