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Title: Temporal confinement and enhancement of high-order harmonic emission with a synthesized laser field

Abstract

We demonstrated that a synthesized laser field consisting of an intense long (45 fs, multi-optical-cycle) laser pulse and a weak short (7 fs, few-optical-cycle) laser pulse can control the electron dynamics and high-order harmonic generation in argon, and generate extreme ultraviolet supercontinuum towards the production of a single strong attosecond pulse. The long pulse offers a large amplitude field, and the short pulse creates a temporally narrow enhancement of the laser field and a gate for the highest energy harmonic emission. This scheme paves the way to generate intense isolated attosecond pulses with strong multi-optical-cycle laser pulses.

Authors:
; ; ; ;  [1]; ; ;  [2];  [1];  [3]
  1. State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, The Chinese Academy of Sciences, Shanghai 201800 (China)
  2. Key Laboratory of Optical and Magnetic Resonance Spectroscopy of Ministry of Education, Department of Physics, East China Normal University, Shanghai 200062 (China)
  3. (China)
Publication Date:
OSTI Identifier:
20982452
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.051802; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; AMPLITUDES; ARGON; CONFINEMENT; ELECTRONS; EMISSION; EXTREME ULTRAVIOLET RADIATION; HARMONIC GENERATION; LASER RADIATION; PULSES

Citation Formats

Xiong, Hui, Li, Ruxin, Zeng, Zhinan, Zheng, Yinghui, Chen, Xiaowei, Peng, Yan, Yang, Xuan, Zeng, Heping, Xu, Zhizhan, and Key Laboratory of Optical and Magnetic Resonance Spectroscopy of Ministry of Education, Department of Physics, East China Normal University, Shanghai 200062. Temporal confinement and enhancement of high-order harmonic emission with a synthesized laser field. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.051802.
Xiong, Hui, Li, Ruxin, Zeng, Zhinan, Zheng, Yinghui, Chen, Xiaowei, Peng, Yan, Yang, Xuan, Zeng, Heping, Xu, Zhizhan, & Key Laboratory of Optical and Magnetic Resonance Spectroscopy of Ministry of Education, Department of Physics, East China Normal University, Shanghai 200062. Temporal confinement and enhancement of high-order harmonic emission with a synthesized laser field. United States. doi:10.1103/PHYSREVA.75.051802.
Xiong, Hui, Li, Ruxin, Zeng, Zhinan, Zheng, Yinghui, Chen, Xiaowei, Peng, Yan, Yang, Xuan, Zeng, Heping, Xu, Zhizhan, and Key Laboratory of Optical and Magnetic Resonance Spectroscopy of Ministry of Education, Department of Physics, East China Normal University, Shanghai 200062. Tue . "Temporal confinement and enhancement of high-order harmonic emission with a synthesized laser field". United States. doi:10.1103/PHYSREVA.75.051802.
@article{osti_20982452,
title = {Temporal confinement and enhancement of high-order harmonic emission with a synthesized laser field},
author = {Xiong, Hui and Li, Ruxin and Zeng, Zhinan and Zheng, Yinghui and Chen, Xiaowei and Peng, Yan and Yang, Xuan and Zeng, Heping and Xu, Zhizhan and Key Laboratory of Optical and Magnetic Resonance Spectroscopy of Ministry of Education, Department of Physics, East China Normal University, Shanghai 200062},
abstractNote = {We demonstrated that a synthesized laser field consisting of an intense long (45 fs, multi-optical-cycle) laser pulse and a weak short (7 fs, few-optical-cycle) laser pulse can control the electron dynamics and high-order harmonic generation in argon, and generate extreme ultraviolet supercontinuum towards the production of a single strong attosecond pulse. The long pulse offers a large amplitude field, and the short pulse creates a temporally narrow enhancement of the laser field and a gate for the highest energy harmonic emission. This scheme paves the way to generate intense isolated attosecond pulses with strong multi-optical-cycle laser pulses.},
doi = {10.1103/PHYSREVA.75.051802},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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  • The concept of heterodyne mixing of laser fields is theoretically applied to the process of high-harmonic generation to enhance and modulate the kinetic energy of the active electron on subcycle time scales. A very small amount of intensity in the heterodyne field creates a significant modification of the electron kinetic energy, due to its amplification by the strong fundamental field in the kinetic-energy term, in which the heterodyne mixing occurs. Quantum calculations are carried out to verify the predictions of the classical results, demonstrating very good qualitative and quantitative agreement. Applications of the heterodyne-mixing concept are the extension of themore » harmonic cutoff to higher photon energies and the temporal gating of attosecond pulse production.« less