Control of the filamentation distance and pattern in long-range atmospheric propagation

Abstract

We use the double-lens setup [10, 11] to achieve a 20-fold delay of the filamentation distance of non-chirped 120 fs pulses propagating in air, from 16m to 330m. At 330m, the collapsing pulse is sufficiently powerful to create plasma filaments. We also show that the scatter of the filaments at 330m can be significantly reduced by tilting the second lens. To the best of our knowledge, this is the longest distance reported in the Literature at which plasma filaments were created and controlled. Finally, we show that the peak power at the onset of collapse is significantly higher with the double-lens setup, compared with the standard negative chirping approach.

Magnetic wiggler-assisted third-harmonic generation of a Gaussian laser pulse in plasma

“…These effects can significantly alter the efficiency of the process. The filamentation of the laser beam can be checked by employing beam-smoothening techniques [23].…”

Self-channeling of high-power laser pulses through strong atmospheric turbulence

“…(8) shows the result of using a negatively chirped Gaussian pulse (W 0 = 1.4 cm) with the scaled turbulence parameters W 0 / 0 = 1 and σ 2 R = 1. 5. The temporal compression of the pulse keeps the power relatively constant over 6 Z R .…”

“…With the advent of laser pulses exceeding gigawatts of peak power, nonlinear self-focusing in air and laser filamentation became possible. Numerous studies have shown that filamentation can produce extended optical and plasma structures in air [3][4][5][6][7]. Filamentation allows the laser pulse to propagate many vacuum Rayleigh lengths at high intensity due to a balancing of nonlinear self-focusing, plasma defocusing or harmonic generation, and nonlinear dispersion.…”

Nitrogen fluorescence induced by the femtosecond intense laser pulses in air

“…In previous works, experimental research in the field of filamentation created filaments typically a few metres in the laboratory [17][18][19] and over hundreds of metres Correspondence to: S. Li and M. Jin, Institute of Atomic and Molecular Physics, Jilin University, Changchun, Jilin Province 130012, China. Email: suyu11@mails.jlu.edu.cn, mxjin@jlu.edu.cn at a range of few kilometres in the atmosphere [20][21][22] , making the remote sensing possible. Since the intensity of plasma fluorescence is related to that of the laser beam, plasma fluorescence spectra along the propagation path can be used to characterize the femtosecond filamentation process.…”