By Robin D. Lopez and Toan Q. Tran
Charles Townes was quoted saying he “knew that the laser would have a huge impact for research” at the recent LSO Workshop at Lawrence Berkeley National Laboratory (LBNL). It’s quite doubtful he foresaw the various applications the laser would have within the next 50 years after his groundbreaking work.
Of course, the potential of the laser was seen. However, its abilities and versatility is truly amazing when one steps back and reflects on the lasers’ actual impact on research and development, currently, and in the future. We recently completed a summer internship at LBNL, witnessing firsthand what lasers are capable of, and will use that experience to demonstrate the wide range of laser applications in R&D.
Grand Uses of Lasers
There are many projects at LBNL, but the following few are the ones that particularly stood out as having high levels of interest and showing the wide range of contributions from laser technology. Examples are 3D image mapping, audio record restoration, improving combustion flames, use as a light source mechanism to observe materials/objects and to measure shock waves. Today we can use lasers to generate “table top” optical accelerators, interaction of a laser and synchrotron beam to generate femtosecond x-ray pulses. There is also the generation of attosecond pulses, terahertz radiation and femtosecond pulse probe work that allows investigation into a wide variety of chemical reactions on the micro and nano scale.
Other projects of interest at LBNL are the second-generation Neutralized Drift Compression eXperiment (NDCX-II) and the Berkeley Lab Laser Accelerator (BELLA) project. Aside from those projects (some of which will be discussed in depth), there is also the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL), another facility we were able to visit, thanks to NIF’s LSO Jamie King and LBNL’s LSO Ken Barat.
Lasers have become an indispensable tool in enabling 3-D imaging of materials, cell colonies and organisms such as plants. Such technology is being utilized regarding bio-diesel fuel research. Many researchers have studied the benefits and process of creating bio-diesel fuel, yet one thing hinders the ability for bio-diesel fuel from becoming more of a mainstream product.
There’s no clear-cut efficient way in producing it. Thus, research has been taken down to microscopic levels, in observing physical and chemical structures of plants, to see if there are any possible connections that can be made in making the production of biodiesel fuel more efficient and hopefully cost effective.
Moreover, another application of lasers is found at NIF. The NIF site is as large as three football fields that contain brilliant scientists, physicists, engineers and technicians that work and test complex systems and equipment that will bring star power to Earth. Large optics, optical coating and large rapid growth crystals (600 pounds) are all produced on site at LLNL that amplify and divide large laser beams into 192 beams that will be focused into a target chamber onto a pellet made of deuterium and tritium enclosed in a small gold cylinder. The laser system will generate about nearly two million joules of ultraviolet laser energy that will heat and compress the pellet to about 100 million degrees and 100 billion times the Earth’s atmosphere that will create an immense discharge of energy otherwise known as fusion. Although the highlight of NIF’s expectation is fusion ignition, which discharges massive amounts of energy to be considered as a resource, the other goals are the conformation of nuclear weapon simulations, the cosmos, materials science and nuclear science.
NIF’s developments wouldn’t have been imaginable without the invention of lasers. As NIF is the forefront of modern laser technology, it is also relevant to consider other significant modern research such as BELLA of the Laser Optics and Accelerator Systems Integrated Studies (L’OASIS) Program of the Accelerator and Fusion Research Division at LBNL, which will also set another milestone that lasers will achieve in science. Project leader Wim Leemans, with BELLA, will develop a series of synchronized laser systems that will accelerate electrons up to 10-GeV (10 billion electron volts) within a relatively short distance (about 1 meter) that will provide an alternative form of an advanced light source and free electron lasers. From this, scientists not only can further study high-energy physics, but also with the use of free-electron lasers, chemists, biologists, materials scientists and researchers will obtain valuable tools to work with in high energy research. Additionally, such lasers could be modified to emit x-ray beams that could be used in the medical field to take very high-resolution x-ray images. The significance of the BELLA project to laser innovation is to provide amazing applications to a variety of advance research. With continued development in laser plasma accelerators, accelerator-based research costs could be radically cut down due to the condense size of these systems such as BELLA.
Restoring The Past
Furthermore, another project conducted at LBNL is the Image, Reconstruct, Erase Noise, Etc. (I.R.E.N.E.) audio restoration project in which discs and cylinders are observed to restore historic recorded sound collections. Researchers achieved the goal of mapping out the surface of the media (records and cylinders). After mapping out the surface grooves, image analysis software is used to play the recorded sounds, based off of the grooves, much how a needle of a phonograph follows the grooves of a record in order to play a particular song. The software emulates the direction of where the needle would go and how the audio would have played. By recreating these audios, it helps to preserve the original pieces, yet still allowing people to enjoy audio recordings from the past. The laser used in this particular project is a Class 1 laser and offers a non-contact method of analyzing the grooves and mapping them out, because if anything were to touch the material, it could alter the surface, thus affecting its grooves. This exemplifies how big of an impact even the most harmless of lasers have on R&D. Hence, lasers offer capabilities unparalleled by any other devices or machines because of its versatility and innovation over the years.