TechTheDay

Laser technology is generally viewed as the pinnacle of light power. Lasers can go over greater distances compared to typical light. Lasers can be made powerful enough to be used in cutting hard materials but they can also be downscaled and tempered to be useful in small applications. To date, the most powerful laser is at the Lawrence Livermore National Laboratory’s National Ignition Facility. It makes use of preamplifiers to increase laser beam energy by up to ten billion times. However, as reported on UA New, optical scientists from the University of Arizona have developed a way to make lasers even stronger and more far-reaching than before.

External Refueling – Enhancing Laser Power

Laser beam are already powerful light beams. However, even the highest intensity lasers produced with modern technology dissipate over a distance of just a few meters. This dissipation makes them lost their power and focus, making them incapable of reaching farther distances with considerable enough power and intensity.

Thanks to a breakthrough made by a University of Arizona research team, lasers can now go farther without losing so much of their intensity through a system wherein high intensity laser is embedded within a second beam at a lower intensity. It’s like laser within a laser, something comparable to a cable covered by another layer of insulation. The lower intensity second beam is being referred to as the “dress beam” while the high intensity laser beam within it is called the “central beam.”

The “dress beam” is used to “refuel” the central laser beam. This refueling system is called “external refueling,” as described in the journal Nature Photonics.

Multimillion Research Project

This multimillion laser research project responsible for this breakthrough in laser technology was funded by the United States Department of Defense through a $7.5 million research grant. It was undertaken by a research team composed of members coming from different scientific disciplines.

The goal of the research project was to make short laser pulses travel over extended distances through the atmosphere without losing intensity. Researchers are aiming to find ways to prevent laser beams from scattering as they strike water droplets and other particles suspended in the atmosphere. High intensity laser inevitably loses intensity and energy as it ionizes the air and produces plasma.

Nevertheless, lasers can “self focus” if they pack high enough energy and are sustained as they travel through the atmosphere. Strengthening the power of laser to a level higher than what older technologies permit can create laser beams that don’t behave in the same way a typical laser beam does. “Self focusing” happens when the peak power of laser pulses surpasses the “critical power” level, leading to “optical filamentation.”

Optical Filamentation

In the state of optical filamentation, laser beams no longer follow linear diffraction. This is what it means to not behave in the same way typical laser beams do. Optical filamentation makes laser travel farther and allows the beam to “ignore” the plasma created by the ionization happening along its course.

Applications

Farther-reaching high intensity laser has a number of practical uses. Two of the immediate applications are the guiding of electric discharges in the atmosphere (lightning formation) and remote sensing.

Short high intensity laser pulses that reach longer distances without significantly weakening can create plasma tracks that can stimulate lightning formation. Hence, it can be used to guide electric discharges in the atmosphere. The plasma tracks created by the powerful laser beam serves as the lightning rod or wire that guides the direction of lightning or at least the area where lightning can take place. As such, it will soon be possible to use laser for lightning diversion.

In the area of remote sensing, this farther-reaching laser tech can be used to generate light reactions in a remote area. These reactions are then analyzed by a ground station to determine the composition of the surrounding air.

Some would think that this new laser technology might be weaponized, as it makes it possible for humans to direct lightning strikes to inimical targets. This is obviously not improbable. If the United States failed to make “weather control” happen; directing lightning strikes could be a good alternative. However such a threat is not enough reason to prevent laser technology from advancing. After all, any form of technology has the potential to serve unmeritorious purposes. Still it’s a good thing knowing that laser technology is progressing and that it can serve a host of good applications.