-Design and construction of prototype N2 laser system
prototype transversely excited (TE) nitrogen laser for energetic nano-scale pulses based on Blumlein and charge transfer discharge techniques
-Characterization and applications
-Design and fabrication of electronic systems for N2 laser systems
-Design simulation using NI Multisim tools
more about N2 laser
Different diagnostics techniques employ to characterize the femtosecond laser systems such as auto-correlation, frequency resolved optical gating (FROG), and cross-correlation frequency resolved optical gating (XFROG). Other complex techniques like spectral phase interferometry for direct electric-field reconstruction (SPIDER) and dispersing a pair of light electric fields (TADPOLE) which is the combination of FROG and SPIDER. The autocorrelation technique fails to provide information about the phase of the pulse. Therefore, the shape of temporal profile guessed before to make the experimental measurements. On the other hand, SPIDER technique can provide spectral and temporal information, but the experimental setup is quite complicated and challenging in the alignment. The FROG technique, which can be described as a spectrally resolved auto-correlation measurement, simple in setup and efficient to characterize the spectral and temporal evolution of the femtosecond pulses. There are different versions of FROG diagnostic techniques; the most sensitive version of FROG is second harmonic generation (SHG) FROG. Further, it can be a categorized into multi-shot FROG and single-shot FROG. The FROG techniques involve the gating of pulse with itself and measured the spectrum versus the delay between the two pulses, while in the XFROG technique a well-known pulse is gated with the unknown measured pulse. The XFROG and FROG techniques gives the phase and pulse intensity versus time or frequency domain.
A Transversely Excited Atmospheric (TEA) nitrogen laser is a pulse mode molecular gas laser. In this arrangement, the whole volume of the gas is excited by a single electric pulse. Normally, N2 gas or air is being used as an active medium in TEA nitrogen laser, and lasing is obtained through electrical discharge of N2 gas or air between two specifically designed electrodes. An ignition system obtains a high potential difference in the laser discharge channel creates a strong electric field in the laser discharge channel which excites the nitrogen molecules because of the fast pumping mechanism from the ground state to the Upper laser level. Population inversion established between the upper laser level and the lower laser level by electron impact excitations. The laser transition occurs by emitting photons in ultraviolet (UV) region corresponding to the transitions from upper laser level to lower laser level. Nitrogen laser has been used to measure the speed of sound in different materials, and to visualize the pulse plasma in the nanosecond range. It has applications in medicine, determination of estrogens using surface-assisted laser desorption, nano-particles based mass spectrometry for biomolecules analysis, deposition of thin films for nonlinear optical applications and characterization of phase change chalcogenide thin film.