- Physical Review Journals
All JournalsPhysics Magazine

Physical Review A

Export citation

Export citation

Choose format for download:

Download Citation

    Ultrafast parametric interactions without the need of broadband phase-matching

    Wentao Zhu1, Yanfang Zhang1, Peng Yuan1,2, Zhipeng Qin1,2, Jing Wang1,2,*, Jingui Ma1,2, Heyuan Zhu3, and Liejia Qian1,2,4

    • 1Key Laboratory for Laser Plasma and IFSA Collaborative Innovation Center, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
    • 2National Key Laboratory of Dark Matter Physics, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
    • 3Key Laboratory of Micro and Nano Photonic Structures, Department of Optical Science and Engineering, Fudan University, Shanghai 200433, China
    • 4Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 201210, China

    • *Contact author: wangj1118@sjtu.edu.cn
    PDF

    Phys. Rev. A 113, 063509 – Published 3 June, 2026

    DOI: https://doi.org/10.1103/8hbk-d6rj

    Abstract

    In conventional quadratic nonlinear interactions with femtosecond lasers, group-velocity mismatch (GVM) is typically regarded as a detrimental effect that restricts the phase-matching bandwidth. Here, we demonstrate a counterintuitive ultrafast parametric process where nonvanished GVMs actively facilitate efficient energy transfer from picosecond pumps to femtosecond signals. The mechanism of such an efficient parametric interaction is revealed: the pump-signal temporal walk off enables traveling-wave difference-frequency generation (DFG), sustaining continuous amplification of the pulse leading edge, while the signal-idler temporal walk off rapidly removes the idler from the interaction region, effectively suppressing back conversion and locking energy into the signal. This process can be implemented in standard collinear Type-II beta-barium-borate (β-BBO) crystals. Numerical simulations confirm 90% pump depletion efficiency while generating amplified femtosecond signals with ∼50 nm bandwidth (6.5 times beyond the conventional phase-matching bandwidth). This work establishes a compact and efficient route to generate high-power femtosecond pulses directly from picosecond laser systems.

    View figure in article

    Physics Subject Headings (PhySH)

    Authorization Required

    We need you to provide your credentials before accessing this content.

    Other Options

    References (Subscription Required)

    Outline

    Information

    Phys. Rev. A 113, 063509– Published 3 June, 2026
    • Received 28 January 2026
    • Accepted 15 May 2026
    Crossmark - Check for updates button

    ©2026 American Physical Society

    Sign In to Your Journals Account

    Filter

    Filter

    Article Lookup

    Enter a citation