Laser Turns 50 (episode 2)

Let there be Light: An Overview of Solid-State Laser Technology (Dr. Tayyab Imran)

From Theodore Maiman’s small ruby laser to ultrafast Ti: Sapphire laser technology, a solid-state laser technology revolution, earning important roles in scientific research,  engineering, medicine, materials working, and a host of other applications.

The Use of Lasers in Opthalmology (Dr. Nadeem H. Butt)
The laser is a special light with variable wavelength and variable effect on different structures of the eyeball. The effects include ablation, disruption, and coagulation. According to the wavelength and effects, the lasers can be grouped as Green laser, YAG laser, Excimer Laser, and CO2 Laser. These Lasers are used for different disorders of the eye which range from disorders of the ocular surface to the disorders deep inside the eyeball including the retina. There are many diseases that used to remain untreated or had interventional and surgical treatments. Most of them can now be treated with ease and comfort on a daycare basis not requiring admission and hospitalization. The Physics, delivery system, uses, effects, and after-effects of lasers will be covered in the presentation.

Laser-Assisted Pump-probe Studies of Atoms (Dr. Aslam Baig)

Laser-assisted spectroscopic techniques have been exploited to study the highly excited states of atoms; a pump-probe experiment. In this technique, at least two dye lasers are required; the first dye laser serves as an exciting laser whereas the second laser serves as an ionizing laser. A Nd:YAG laser SHG (533nm, 500 mJ) and THG (355 nm, 200 mJ) is used to pump the TDL-90 dye laser (line width »0.08 cm^-1) and locally fabricated dye lasers (line width »0.25 cm^-1) for multi-step or multi-photon excitation/ ionization of atoms. The ions are detected either in a thermionic diode ion detector or in an atomic beam apparatus. We have also utilized the polarization properties of the laser beams to measure the photoionization cross-sections of the excited states of atoms. A few examples of the spectra will be presented in addition to the latest experimental results on the photoionization of atoms from the Free Electron Laser Source (FLASH).