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

Journal of Physics B Atomic Molecular and Optical Physics

Macroscopic effects on the broadband supercontinuum driven by an ω and ω/2 bichromatic laser pulse

Qianguang Li, Peixiang Lu, Pengfei Lan, Weiyi Hong, Qingbin Zhang

Published Jul 22, 2009• 6 citations
Publisher

Abstract

The macroscopic effects on the broadband supercontinuum generated in the interaction of an ω and ω/2 bichromatic laser pulse and an atom are investigated with a three-dimensional propagation model. It is shown that a broadband supercontinuum can still be generated when the macroscopic effects are included, and the macroscopic effects can ameliorate the temporal characteristic of the broadband supercontinuum of a single atom. When the broadband supercontinuum propagates through the low-density gas medium, the modulations of the broadband supercontinuum can be weakened or even eliminated by phase matching. Moreover, this unmodulated broadband supercontinuum can steadily last for a relative long distance of propagation and can be directly filtered to generate an isolated sub-100 attosecond pulse.

DOI
10.1088/0953-4075/42/16/165601

Related papers

Propagation effects of isolated attosecond pulse generation with a multicycle chirped and chirped-free two-color field

Hongchuan Du, Bitao Hu

We present a theoretical study of isolated attosecond pulse generation with a multicycle chirped and chirped-free two-color field. We show that the bandwidth of the extreme ultraviolet supercontinuum can be extended by combining a multicycle chirped pulse and a multicycle chirped-free pulse. Also, the broadband supercontinuum can still be generated when the macroscopic effects are included. Furthermore, the macroscopic effects can ameliorate the temporal characteristic of the broadband supercontinuum of the single atom, and eliminate the modulations of the broadband supercontinuum. Thus a very smooth broadband supercontinuum and a pure isolated 102-as pulse can be directly obtained. Moreover, the structure of the broadband supercontinuum can be steadily maintained for a relative long distance after a certain distance.

Physical Review A•Aug 12, 2011•36 citations

Isolated attosecond pulse generation from pre-excited medium with a chirped and chirped-free two-color field

Hongchuan Du, Laoyong Luo, Xiaoshan Wang +1 more

We theoretically investigate the isolated attosecond pulse generation from pre-excited medium with a chirped and chirped-free two-color field. It is found that the large initial population of the excited state can lead to the high density of the free electrons in the medium and the large distortion of the driving laser field after propagation, though it benefits large enhancement of harmonic intensity in single atom response. These effects can weaken the phase-match of the macroscopic supercontinuum. On the contrary, the small initial population of 4% can generate well phase-match intense supercontinuum. We also investigate an isolated attosecond pulse generation by using a filter centered on axis to select the harmonics in the far field. Our results reveal that the radius of the spatial filter should be chosen to be small enough to reduce the duration of the isolated attosecond pulse due to the curvature effect of spatiotemporal profiles of the generated attosecond pulses in the far field.

Optics Express•Apr 13, 2012•21 citations

Generation of bright quantum high-order harmonic driven by combined coherent and bright squeezed vacuum light

Wentao Wang, Yaoshun Sun, Liyuan Wang +6 more

Attosecond quantum light, formed by the superposition of high-order harmonics driven by intense quantum light, opens new routes to probe quantum-mechanical correlations in matter. In this study, we have investigated the macroscopic propagation effects of quantum high-order harmonics generated by the combination of strong coherent and weak bright squeezed vacuum (BSV) lasers interacting with atomic gas. Our results reveal that the pressure-dependent intensity of harmonics arising from absorbing or emitting BSV photons differs from that of harmonics generated using only strong coherent pulses. Macroscopic propagation simulations indicate that the action phase of harmonics is perturbed by the weak BSV pulses. This perturbation modulates the phase mismatch of sub-cycle attosecond bursts and affects their quantum properties when the gas pressure varies. The ability to generate bright quantum high-order harmonics lays a foundation for the establishment and application of attosecond quantum spectroscopy.

quant-pharXiv:2607.20941•Jul 24, 2026•0 citations

Broadband xuv supercontinuum generation via controlling quantum paths by a low-frequency field

Weiyi Hong, Peixiang Lu, Pengfei Lan +3 more

We propose a method to generate broadband extreme ultraviolet supercontinuum harmonics by using the combination of a phase-stabilized few-cycle laser pulse and a low-frequency field. It is shown that this method can significantly modulate the quantum paths of the harmonics. The harmonic spectrum is extended to ${I}_{p}+8.2{U}_{p}$ and harmonics with a bandwidth of $4{U}_{p}$ become continuous. By adjusting the carrier-envelope phase of the few-cycle pulse, a close-to-Fourier-limit sub-50-as pulse is straightforwardly obtained.

Physical Review A•Mar 14, 2008•46 citations

Generation of bright quantum high-order harmonic driven by combined coherent and bright squeezed vacuum light

Sizuo Luo, Wentao Wang, Y W Sun +6 more

Abstract Attosecond quantum light, formed by the superposition of high-order harmonics driven by intense quantum light, opens new routes to probe quantum-mechanical correlations in matter. In this study, we have investigated the macroscopic propagation effects of quantum high-order harmonics generated by the combination of strong coherent and weak bright squeezed vacuum (BSV) lasers interacting with atomic gas. Our results reveal that the pressure-dependent intensity of harmonics arising from absorbing or emitting BSV photons differs from that of harmonics generated using only strong coherent pulses. Macroscopic propagation simulations indicate that the action phase of harmonics is perturbed by the weak BSV pulses. This perturbation modulates the phase mismatch of sub-cycle attosecond bursts and affects their quantum properties when the gas pressure varies. The ability to generate bright quantum high-order harmonics lays a foundation for the establishment and application of attosecond quantum spectroscopy.

•Jul 17, 2026•0 citations

Modulation of supercontinuum generation and formation of an attosecond pulse from a generalized two-level medium

Ke Zhao, Ji‐Cai Liu, Chuan‐Kui Wang +1 more

The propagation of ultrashort pulses in a generalized two- level system, consisting of permanent dipole moments, is simulated by solving the full Maxwell - Bloch equations. Special attention has be ...

Journal of Physics B Atomic Molecular and Optical Physics•Mar 26, 2007•2 citations
The macroscopic effects on the broadband supercontinuum generated in the interaction of an ω and ω/2 bichromatic laser pulse and an atom are investigated with a three-dimensional propagation model. It is shown that a broadband supercontinuum can still be generated when the macroscopic effects are included, and the macroscopic effects can ameliorate the temporal characteristic of the broadband supercontinuum of a single atom. When the broadband supercontinuum propagates through the low-density gas medium, the modulations of the broadband supercontinuum can be weakened or even eliminated by phase matching. Moreover, this unmodulated broadband supercontinuum can steadily last for a relative long distance of propagation and can be directly filtered to generate an isolated sub-100 attosecond pulse.
We present a theoretical study of isolated attosecond pulse generation with a multicycle chirped and chirped-free two-color field. We show that the bandwidth of the extreme ultraviolet supercontinuum can be extended by combining a multicycle chirped pulse and a multicycle chirped-free pulse. Also, the broadband supercontinuum can still be generated when the macroscopic effects are included. Furthermore, the macroscopic effects can ameliorate the temporal characteristic of the broadband supercontinuum of the single atom, and eliminate the modulations of the broadband supercontinuum. Thus a very smooth broadband supercontinuum and a pure isolated 102-as pulse can be directly obtained. Moreover, the structure of the broadband supercontinuum can be steadily maintained for a relative long distance after a certain distance.
We theoretically investigate the isolated attosecond pulse generation from pre-excited medium with a chirped and chirped-free two-color field. It is found that the large initial population of the excited state can lead to the high density of the free electrons in the medium and the large distortion of the driving laser field after propagation, though it benefits large enhancement of harmonic intensity in single atom response. These effects can weaken the phase-match of the macroscopic supercontinuum. On the contrary, the small initial population of 4% can generate well phase-match intense supercontinuum. We also investigate an isolated attosecond pulse generation by using a filter centered on axis to select the harmonics in the far field. Our results reveal that the radius of the spatial filter should be chosen to be small enough to reduce the duration of the isolated attosecond pulse due to the curvature effect of spatiotemporal profiles of the generated attosecond pulses in the far field.
Attosecond quantum light, formed by the superposition of high-order harmonics driven by intense quantum light, opens new routes to probe quantum-mechanical correlations in matter. In this study, we have investigated the macroscopic propagation effects of quantum high-order harmonics generated by the combination of strong coherent and weak bright squeezed vacuum (BSV) lasers interacting with atomic gas. Our results reveal that the pressure-dependent intensity of harmonics arising from absorbing or emitting BSV photons differs from that of harmonics generated using only strong coherent pulses. Macroscopic propagation simulations indicate that the action phase of harmonics is perturbed by the weak BSV pulses. This perturbation modulates the phase mismatch of sub-cycle attosecond bursts and affects their quantum properties when the gas pressure varies. The ability to generate bright quantum high-order harmonics lays a foundation for the establishment and application of attosecond quantum spectroscopy.
We propose a method to generate broadband extreme ultraviolet supercontinuum harmonics by using the combination of a phase-stabilized few-cycle laser pulse and a low-frequency field. It is shown that this method can significantly modulate the quantum paths of the harmonics. The harmonic spectrum is extended to Ip+8.2Up{I}_{p}+8.2{U}_{p}Ip​+8.2Up​ and harmonics with a bandwidth of 4Up4{U}_{p}4Up​ become continuous. By adjusting the carrier-envelope phase of the few-cycle pulse, a close-to-Fourier-limit sub-50-as pulse is straightforwardly obtained.
Abstract Attosecond quantum light, formed by the superposition of high-order harmonics driven by intense quantum light, opens new routes to probe quantum-mechanical correlations in matter. In this study, we have investigated the macroscopic propagation effects of quantum high-order harmonics generated by the combination of strong coherent and weak bright squeezed vacuum (BSV) lasers interacting with atomic gas. Our results reveal that the pressure-dependent intensity of harmonics arising from absorbing or emitting BSV photons differs from that of harmonics generated using only strong coherent pulses. Macroscopic propagation simulations indicate that the action phase of harmonics is perturbed by the weak BSV pulses. This perturbation modulates the phase mismatch of sub-cycle attosecond bursts and affects their quantum properties when the gas pressure varies. The ability to generate bright quantum high-order harmonics lays a foundation for the establishment and application of attosecond quantum spectroscopy.