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

Physical review. B, Condensed matter

Influence of population decay on the short time signal in four-wave mixing experiments

J. P. Lavoine, Alex Boeglin

Published Feb 15, 2000• 2 citations
Publisher

Abstract

Oscillatory dephasing is a characteristic of non-Markovian relaxation phenomena when the coherence losses are essentially due to pure dephasing processes. In this paper, we wish to consider the case where the phase relaxation is essentially due to population decay. To this end, we calculate the transient four-wave mixing signal in the short pulse limit from a three-level sytem nondiagonally coupled to a bath of harmonic oscillators. We will show that no oscillatory dephasing is observed in the non-Markovian regime, only a nonexponential decay. Therefore, oscillatory dephasing appears to be a signature of pure dephasing processes.

DOI
10.1103/physrevb.61.5254

Related papers

Oscillatory dephasing in the presence of inhomogeneous broadening

P. Martin, J. P. Lavoine, Alex Boeglin +1 more

Oscillatory dephasing is a characteristic signature of non-Markovian relaxation phenomena. From its analysis one can obtain valuable information about the dynamics of the surroundings of a given system. In this paper we calculate the transient four-wave mixing signal in the short pulse limit from two-level systems coupled to a bath of harmonic oscillators for arbitrary coupling strengths and in the presence of inhomogeneous broadening. The strong and weak coupling cases having already been analyzed, we focus on the study of the intermediate case where oscillatory dephasing is observed. We specifically show that even in the presence of inhomogeneous broadening, information about the surroundings can still be extracted in the intermediate coupling regime. The formation and the evolution of the photon echo in such experiments are also analyzed. \textcopyright{} 1996 The American Physical Society.

Physical review. B, Condensed matter•Nov 15, 1996•2 citations

Non-Markovian effects on quantum beats

J. P. Lavoine, Alex Boeglin, P. Martin +1 more

The transient four-wave mixing signal from a three-level system coupled to a bath of harmonic oscillators is calculated in the short-pulse limit. This allows an examination of the non-Markovian effects on the relaxation processes in the excited levels between which beating occurs. In particular, it is possible to distinguish between oscillations which are due to oscillatory dephasing, a consequence of the memory effects, and oscillations due to the quantum beats. This also allows one to analyze how these two kinds of oscillations are mixed together. We show that we not only have an amplitude modulation of the beats as in the Markovian case but also deformations of the beats for short delays between the exciting light pulses. These deformations are a consequence of the nonequilibrium motion of the surroundings of the system under optical excitation. \textcopyright{} 1996 The American Physical Society.

Physical review. B, Condensed matter•May 1, 1996•9 citations

Nonadiabatic coupling effects on the short time signal in four-wave mixing experiments

J. P. Lavoine, Alex Boeglin

The transient four-wave mixing signal from a three-level system coupled to a bath of harmonic oscillators is calculated in the short-pulse limit and analyzed at short times. The two excited states of the system are coupled by a constant nonadiabatic interaction V which is treated exactly. This allows an examination of the influence of V on the dynamics in the excited levels at short times. We show that the positions of the minima of the potential energy surfaces of the excited states with respect to the one of the fundamental state play an important role in the relaxation processes. We also show that for high nonadiabatic coupling it is possible to minimize the effect of the bath and hence to minimize, at short times, the coherence losses of the system. The identification of the molecular parameters required to take advantage of this effect should be of interest in the selection of materials for applications in nonlinear optics.

The Journal of Chemical Physics•Apr 17, 2003•2 citations

Influence of non-Markovian effects in degenerate four-wave-mixing processes

J. P. Lavoine, A. A. Villaeys

In this work, we analyze the influence of non-Markovian effects on a pulsed time-delayed four-wave-mixing experiment. By using a perturbative approach the density matrix equations are solved for a medium modeled by two-level systems and excited by short pulses. We show that the intensity of the diffracted light can be expressed as a simple function of the bath memory function. This demonstrates the interest of such an experiment to get information on the bath.

Physical Review Letters•Nov 1, 1991•9 citations

FWM in optically dense medía

Opher Kinrol, Yehiam Prior

We show, both experimentally and theoretically, that short-pulse reshaping clue to propagation leads to the formation of negative-time-delay signals in four-wave mixing (FWM) and to apparent signal decay that is not given by the dephasing or the population-decay rates. Recently, pulse reshaping due to coherent propagation was used to estimate dephasing times in CD, and ZnP·. (Ref. 1), and negative time-delay response in FWM in quantum wells was reported and was explained in terms of higher-order susceptibilities interfering with the third-order FWM process.2

•May 8, 1994•0 citations

Pure dephasing induced by exciton-phonon interactions in GaAs quantum dots

Hailin Wang, Xudong Fan, T. Takagahara +1 more

Summary form only given.We report studies of exciton dephasing in quantum dot (QD)-like islands in narrow GaAs quantum wells (QWs). Using three pulse transient four-wave mixing (FWM), we compare dephasing rates directly with population decay rates. This comparison reveals a pure dephasing process that dominates excitonic dephasing at elevated temperatures but does not involve exciton population relaxation.

Conference on Lasers and Electro-Optics•Nov 27, 2002•0 citations
Oscillatory dephasing is a characteristic of non-Markovian relaxation phenomena when the coherence losses are essentially due to pure dephasing processes. In this paper, we wish to consider the case where the phase relaxation is essentially due to population decay. To this end, we calculate the transient four-wave mixing signal in the short pulse limit from a three-level sytem nondiagonally coupled to a bath of harmonic oscillators. We will show that no oscillatory dephasing is observed in the non-Markovian regime, only a nonexponential decay. Therefore, oscillatory dephasing appears to be a signature of pure dephasing processes.
Oscillatory dephasing is a characteristic signature of non-Markovian relaxation phenomena. From its analysis one can obtain valuable information about the dynamics of the surroundings of a given system. In this paper we calculate the transient four-wave mixing signal in the short pulse limit from two-level systems coupled to a bath of harmonic oscillators for arbitrary coupling strengths and in the presence of inhomogeneous broadening. The strong and weak coupling cases having already been analyzed, we focus on the study of the intermediate case where oscillatory dephasing is observed. We specifically show that even in the presence of inhomogeneous broadening, information about the surroundings can still be extracted in the intermediate coupling regime. The formation and the evolution of the photon echo in such experiments are also analyzed. \textcopyright{} 1996 The American Physical Society.
The transient four-wave mixing signal from a three-level system coupled to a bath of harmonic oscillators is calculated in the short-pulse limit. This allows an examination of the non-Markovian effects on the relaxation processes in the excited levels between which beating occurs. In particular, it is possible to distinguish between oscillations which are due to oscillatory dephasing, a consequence of the memory effects, and oscillations due to the quantum beats. This also allows one to analyze how these two kinds of oscillations are mixed together. We show that we not only have an amplitude modulation of the beats as in the Markovian case but also deformations of the beats for short delays between the exciting light pulses. These deformations are a consequence of the nonequilibrium motion of the surroundings of the system under optical excitation. \textcopyright{} 1996 The American Physical Society.
The transient four-wave mixing signal from a three-level system coupled to a bath of harmonic oscillators is calculated in the short-pulse limit and analyzed at short times. The two excited states of the system are coupled by a constant nonadiabatic interaction V which is treated exactly. This allows an examination of the influence of V on the dynamics in the excited levels at short times. We show that the positions of the minima of the potential energy surfaces of the excited states with respect to the one of the fundamental state play an important role in the relaxation processes. We also show that for high nonadiabatic coupling it is possible to minimize the effect of the bath and hence to minimize, at short times, the coherence losses of the system. The identification of the molecular parameters required to take advantage of this effect should be of interest in the selection of materials for applications in nonlinear optics.
We show, both experimentally and theoretically, that short-pulse reshaping clue to propagation leads to the formation of negative-time-delay signals in four-wave mixing (FWM) and to apparent signal decay that is not given by the dephasing or the population-decay rates. Recently, pulse reshaping due to coherent propagation was used to estimate dephasing times in CD, and ZnP·. (Ref. 1), and negative time-delay response in FWM in quantum wells was reported and was explained in terms of higher-order susceptibilities interfering with the third-order FWM process.2