Laser pulse compression up to few-cycle durations in multicore fiber

Area of Science:

• Optics and Photonics
• Nonlinear Fiber Optics
• Laser Physics

Background:

• High-intensity ultrashort laser pulses are crucial for various scientific applications.
• Achieving significant laser pulse compression with high energy efficiency remains a challenge.

Purpose of the Study:

• To propose and investigate a novel mechanism for self-compression of laser pulses within a multicore fiber.
• To achieve chirp-free and pedestal-free soliton-like pulses through nonlinear radiation combining.

Main Methods:

• Utilizing a multicore fiber with a central core surrounded by other cores in a ring.
• Employing nonlinear combining of radiation from multiple cores to trap into the central core.
• Numerical simulations to demonstrate the feasibility and performance of the proposed mechanism.

Main Results:

• A compression ratio of approximately 6 was achieved with nearly 100% energy efficiency.
• The compression ratio showed weak dependence on pulse energy and the number of cores.
• An enhanced compression ratio of up to 40 was demonstrated with over 50% efficiency by compressing longer pulses.
• Numerical simulations confirmed a 38-fold compression to 15 fs with 4 nJ pulse energy using realistic fiber parameters.

Conclusions:

• The proposed mechanism offers an efficient method for laser pulse self-compression in multicore fibers.
• This technique enables the generation of ultrashort, high-quality laser pulses with potential applications in various fields.
• The demonstrated numerical results highlight the practical viability of this approach for achieving femtosecond pulse durations.