arXiv subjects

Arthur Dogariu

Publications and source records attributed to Arthur Dogariu.

2 recordsLinked to original sources

arXiv2025

Calibration of hydrogen atoms measurement using femtosecond two-photon laser induced fluorescence

A new calibration method for H-fs-TALIF is proposed, and the ratio of two-photon absorption cross-sections, $σ^{(2)}$, for atomic hydrogen (H) and krypton (Kr) is determined for the broadband emission of a femtosecond laser system. The estimated ratio of the two-photon absorption cross-sections for H and Kr is $σ^{(2)}$ for H and Kr $σ^{(2)}$(Kr)/$σ^{(2)}$(H) = $0.027\pm 20$%, which is nearly twenty times lower than values previously obtained with narrowband nanosecond lasers. This discrepancy highlights the need for independent calibration of TALIF measurements for a specific laser pulsewidth range.

physics.atom-ph↗

arXiv2010

High gain backward lasing in air

The need for molecular standoff detection has motivated the development of a remotely pumped, high gain air laser that produces lasing in the backward direction and can sample the air as the beam returns. High gain is achieved in the near infrared following pumping with a focused ultraviolet laser. The pumping mechanism is simultaneous resonant two-photon dissociation of molecular oxygen and resonant two-photon pumping of the atomic oxygen fragments. The high gain from the millimeter length focal zone leads to equally strong lasing in the forward and backward directions. Further backward amplification is achieved using prior laser spark dissociation.

physics.optics↗