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 A

Propagation effects in two-color coherent-control processes

Ce Chen, Daniel S. Elliott

Published Jan 1, 1996• 17 citations
Publisher

Abstract

We have investigated a two-color coherent-control process at high densities of the absorbing medium. Irradiating a vapor of atomic mercury with a coherent field, with one component nearly resonant with the three-photon 6s${\mathrm{}}^{1}$${\mathit{S}}_{0}$\ensuremath{\rightarrow}6p${\mathrm{}}^{1}$${\mathit{P}}_{1}^{\mathit{o}}$ transition, and the other component the third harmonic of the first, we observe the interference between the two excitation pathways for this transition. Measurements of this interaction as the density of the mercury vapor is increased show evidence of nonlinear coupling (phase and amplitude locking) of the two field components with each other. This is manifested as a decrease in the magnitude of the photoionization signal, as well as a decrease of the depth of modulation of the photoionization signal. \textcopyright{} 1996 The American Physical Society.

DOI
10.1103/physreva.53.272

Related papers

Phase-sensitive multiphoton ionization

Ce Chen, Yi-Yian Yin, Daniel S. Elliott

We have demonstrated an interference between multiphoton ionization processes that results in a phase-sensitive enhancement or inhibition of the net ionization rate. We focus two laser beams, either of which can induce an atomic transition between the same two states, into a cell containing atomic mercury. One of the fields is at a wavelength of 185 nm and can linearly induce the 6s 1S0 → 6p 1P1 transition in mercury. The other field is at a wavelength precisely three times as long, and it can excite the 6p resonance by a three-photon process. The absorption of two additional visible photons ionizes the mercury. In the presence of both fields, the transition amplitudes interfere, and their relative phases become very important. Their phases can be controlled by controlling the phases of the optical fields inducing the transitions. Coherence between the two fields, vital for the interference, is ensured by generating one field from the other using a nonlinear third-harmonic process. We have also demonstrated the effect of spatial phase variations between the two fields on the local photo-ionization rate.

Annual Meeting Optical Society of America•Jan 1, 1990•0 citations

Interference between different optical processes

Ce. Chen

This thesis reports an experimental study of an interference phenomenon between one-photon and three-photon 6s$\sp1$S$\sb0$-6p$\sp1$P$\sb1$ transition amplitudes in a vapor of atomic mercury. The interference was observed by monitoring the multiphoton ionization signal. Using a three-cell design we were able to separate the third-harmonic generation process and the interfering absorption processes such that we could externally control the relative phase between the two transition amplitudes and directly study the interference phenomena. We observed that the multiphoton ionization signal, which is a measure of the net transition moment, varied sinusoidally as the relative phase increased. Using an eight-electrode design to collect the electrons ionized at different positions along the beam axis around the focal region, we measured the phase shift of the interference due to the $\pi$ phase shift of a focused Gaussian beam propagating through the focal region. The experimental setup and the experimental procedure are discussed in detail. This new method can be used in the study of many phase sensitive processes including potential applications in coherent control of chemical reactions.

•Jan 1, 1991•0 citations

Interference between optical transitions

Ce Chen, Yi-Yian Yin, Daniel S. Elliott

We report observations of an interference between optical transition amplitudes for linear and nonlinear excitation of the mercury 6s $^{1}\mathrm{S}_{0}$\ensuremath{\rightarrow}6p $^{1}\mathrm{P}_{1}$ transition. The transition probability is varied sinusoidally by changing the relative phase of the two fields inducing these distinct processes.

Physical Review Letters•Jan 29, 1990•315 citations

Phase-controlled quantum interference in two-color atomic photoionization

Stefano Cavalieri, R. Eramo, Lorenzo Fini

We report evidence of an interference process between two bound-free atomic transitions induced by laser fields. Sodium atoms, initially prepared in the ${3\mathrm{P}}_{1\mathrm{/}2}$ excited state, are ionized by a nonresonant three-photon interaction with 1064-nm laser light and by a one-photon interaction with the third-harmonic field, at 355 nm. Interference between the two transition paths allows the control of the total ionization rate by varying the relative phase of the laser fields. The experiment has provided a fringe visibility as high as 42%.

Physical Review A•Apr 1, 1997•20 citations

Electronic phase-locking for three-color two-pathway coherent control

Jonah Quirk, Carol E. Tanner, Daniel S. Elliott

We report a new method of two-pathway coherent control using three narrow-band cw laser sources, phase locked in an optical phase-lock loop, to maintain the high degree of optical coherence required for the coherent control process. In addition, we derive expressions for two-photon transition amplitudes and demonstrate their dependence on the polarization of the field components. This phase-locking technique expands the set of interactions to which coherent control techniques may be applied. It also allows for a constant low-frequency offset between the optical interactions, producing a continuous and constant phase ramp between the interactions, facilitating phase-sensitive detection of the modulating atomic signal. We illustrate this technique with two-photon vs.~one-photon excitation of a $ΔF = 1$ component, and alternatively a $ΔF = 0$ component, of the $6s \: ^2S_{1/2} \rightarrow 7s \: ^2S_{1/2}$ transition of atomic cesium.

arXiv:2510.08205•Physical Review A•Jan 13, 2026•0 citations

Coherent control of atomic photoionization

Stefano Cavalieri, R. Eramo, Luca Fini +1 more

Coherent control provides a quantum interference based method for controlling atomic and molecular dynamics. We report two experimental observations of different ways to achieve such a control in atomic photoionization continuum. One is the photoionization of sodium atoms, initially prepared in the 3P1/2 excited state, by a non resonant three-photon interaction with 1064-nm laser light and by a one-photon interaction with the third-harmonic field, at 355 nm. Interference between the two transition paths allows the control of the total ionization rate by varying the relative phase of the laser fields. The second experiment is the observation of the modification of the ionization continua of xenon through laser induced continuum structure (LICS). The multiphoton radiative decay of the xenon ground state into the two electronic continua, that correspond to the two fine structure levels of the ground state of the xenon ion, is varied by electromagnetically embedding a bound state of the atom into the two continua. Both experiments are performed on an atomic beam apparatus which uses a time-of-flight spectrometer for energy analyzing the emitted photoelectrons.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 21, 1998•0 citations
We have investigated a two-color coherent-control process at high densities of the absorbing medium. Irradiating a vapor of atomic mercury with a coherent field, with one component nearly resonant with the three-photon 6s{\mathrm{}}^{1}$${\mathit{S}}_{0}\ensuremath{\rightarrow}6p{\mathrm{}}^{1}$${\mathit{P}}_{1}^{\mathit{o}} transition, and the other component the third harmonic of the first, we observe the interference between the two excitation pathways for this transition. Measurements of this interaction as the density of the mercury vapor is increased show evidence of nonlinear coupling (phase and amplitude locking) of the two field components with each other. This is manifested as a decrease in the magnitude of the photoionization signal, as well as a decrease of the depth of modulation of the photoionization signal. \textcopyright{} 1996 The American Physical Society.
We have demonstrated an interference between multiphoton ionization processes that results in a phase-sensitive enhancement or inhibition of the net ionization rate. We focus two laser beams, either of which can induce an atomic transition between the same two states, into a cell containing atomic mercury. One of the fields is at a wavelength of 185 nm and can linearly induce the 6s 1S0 → 6p 1P1 transition in mercury. The other field is at a wavelength precisely three times as long, and it can excite the 6p resonance by a three-photon process. The absorption of two additional visible photons ionizes the mercury. In the presence of both fields, the transition amplitudes interfere, and their relative phases become very important. Their phases can be controlled by controlling the phases of the optical fields inducing the transitions. Coherence between the two fields, vital for the interference, is ensured by generating one field from the other using a nonlinear third-harmonic process. We have also demonstrated the effect of spatial phase variations between the two fields on the local photo-ionization rate.
This thesis reports an experimental study of an interference phenomenon between one-photon and three-photon 6s$\sp1$S$\sb0$-6p$\sp1$P$\sb1$ transition amplitudes in a vapor of atomic mercury. The interference was observed by monitoring the multiphoton ionization signal. Using a three-cell design we were able to separate the third-harmonic generation process and the interfering absorption processes such that we could externally control the relative phase between the two transition amplitudes and directly study the interference phenomena. We observed that the multiphoton ionization signal, which is a measure of the net transition moment, varied sinusoidally as the relative phase increased. Using an eight-electrode design to collect the electrons ionized at different positions along the beam axis around the focal region, we measured the phase shift of the interference due to the π\piπ phase shift of a focused Gaussian beam propagating through the focal region. The experimental setup and the experimental procedure are discussed in detail. This new method can be used in the study of many phase sensitive processes including potential applications in coherent control of chemical reactions.
We report observations of an interference between optical transition amplitudes for linear and nonlinear excitation of the mercury 6s 1S0^{1}\mathrm{S}_{0}1S0​\ensuremath{\rightarrow}6p 1P1^{1}\mathrm{P}_{1}1P1​ transition. The transition probability is varied sinusoidally by changing the relative phase of the two fields inducing these distinct processes.
We report evidence of an interference process between two bound-free atomic transitions induced by laser fields. Sodium atoms, initially prepared in the 3P1/2{3\mathrm{P}}_{1\mathrm{/}2}3P1/2​ excited state, are ionized by a nonresonant three-photon interaction with 1064-nm laser light and by a one-photon interaction with the third-harmonic field, at 355 nm. Interference between the two transition paths allows the control of the total ionization rate by varying the relative phase of the laser fields. The experiment has provided a fringe visibility as high as 42%.
We report a new method of two-pathway coherent control using three narrow-band cw laser sources, phase locked in an optical phase-lock loop, to maintain the high degree of optical coherence required for the coherent control process. In addition, we derive expressions for two-photon transition amplitudes and demonstrate their dependence on the polarization of the field components. This phase-locking technique expands the set of interactions to which coherent control techniques may be applied. It also allows for a constant low-frequency offset between the optical interactions, producing a continuous and constant phase ramp between the interactions, facilitating phase-sensitive detection of the modulating atomic signal. We illustrate this technique with two-photon vs.~one-photon excitation of a ΔF=1ΔF = 1ΔF=1 component, and alternatively a ΔF=0ΔF = 0ΔF=0 component, of the 6s 2S1/2→7s 2S1/26s \: ^2S_{1/2} \rightarrow 7s \: ^2S_{1/2}6s2S1/2​→7s2S1/2​ transition of atomic cesium.
Coherent control provides a quantum interference based method for controlling atomic and molecular dynamics. We report two experimental observations of different ways to achieve such a control in atomic photoionization continuum. One is the photoionization of sodium atoms, initially prepared in the 3P1/2 excited state, by a non resonant three-photon interaction with 1064-nm laser light and by a one-photon interaction with the third-harmonic field, at 355 nm. Interference between the two transition paths allows the control of the total ionization rate by varying the relative phase of the laser fields. The second experiment is the observation of the modification of the ionization continua of xenon through laser induced continuum structure (LICS). The multiphoton radiative decay of the xenon ground state into the two electronic continua, that correspond to the two fine structure levels of the ground state of the xenon ion, is varied by electromagnetically embedding a bound state of the atom into the two continua. Both experiments are performed on an atomic beam apparatus which uses a time-of-flight spectrometer for energy analyzing the emitted photoelectrons.