| Title |
In situ acoustic monitoring of focused femtosecond pulse duration in air |
| Authors |
Meškėlaitė, Indrė ; Huang, Hsin-Hui ; Mu, Haoran ; Le, Nguyen Hoai An ; Katkus, Tomas ; Aleksandravičius, Edvinas ; Kontenis, Gabrielius ; Paipulas, Domas ; Juodkazis, Saulius ; Gailevičius, Darius |
| DOI |
10.1002/lpor.202600002 |
| Full Text |
|
| Is Part of |
Laser and photonics reviews.. Weinheim : Wiley-VCH GmbH. 2026, Early Access, p. [1-11].. ISSN 1863-8880. eISSN 1863-8899 |
| Keywords [eng] |
acoustic pressure ; chirp control ; femtosecond ; plasma temperature ; pulse compression |
| Abstract [eng] |
The monitoring of the acoustic amplitude of an air breakdown at the focus of the femtosecond laser pulse was used to determine the pulse duration using a computer microphone. Pulse duration was tuned using the chirp settings of a femtosecond laser and measured by an autocorrelator before the focusing optics, where the (Formula presented.) fs pulses were compressed down to (Formula presented.) fs ((Formula presented.) -Photonics compression unit). The amplitude of the acoustic signal scaled with the pulse duration (Formula presented.) as (Formula presented.) in the range from 50 fs to 2 ps. The acoustic signal showed (Formula presented.) dependence on the pulse energy (Formula presented.), which was the same for the shortest (50 fs) and longer (250 fs) pulses widely used in laser machining and 3D nano/microprinting. This scaling is consistent with the electron–ion scattering defined by the electron temperature in the air breakdown plasma (Formula presented.). The demonstrated principle that the sound of air breakdown can be used to measure the pulse duration (50 fs–5 ps) is promising for femtosecond laser pulses at different wavelengths, where second-harmonic autocorrelators are not available. |
| Published |
Weinheim : Wiley-VCH GmbH |
| Type |
Journal article |
| Language |
English |
| Publication date |
2026 |
| CC license |
|
