In scientific research today, lasers literally have limitless application, allowing scientists and researchers to gain deeper insight in the minuscule and the majuscule, and giving them the ability to harvest and analyze clean, dependable data in quantities heretofore unrealized. Here is just a short list of uses for lasers in scientific research:
Astronomy: Dye lasers are used to create artificial laser guide stars, used as parallax reference objects for adaptive optics telescopes for astronomical research.
Earth Sciences: Laser based Light Detection And Ranging (LIDAR) technology has application in geology, seismology, remote sensing and meteorological research.
Laser cooling: First theorized in 1924 by Satyendra Bose and Albert Einstein, this process involves directing particular wavelengths of laser light at atomic ions confined in a specially shaped arrangement of electric and magnetic fields. The laser light slows the ions down, continuously cooling them until absolute zero is reached. As this process is continued, the ions all are slowed and have the same energy level, forming an unusual state of matter known as photon BEC (Bose-Einstein Condensate) and first successfully observed in a laboratory in 2010.
Microscopy: Confocal laser scanning microscopy enables the reconstruction of three-dimensional structures. This technique has gained popularity in the scientific communities. Typical applications are in life sciences, semiconductor inspection and materials science. Two-photon excitation microscopy makes use of lasers to obtain blur-free images of living tissue at very high depths (up to 1mm).
Nuclear fusion: Through a technique known as “inertial confinement fusion,” researchers are using the most powerful and complex arrangements of multiple lasers and optical amplifiers to produce extremely high intensity pulses of light of extremely short duration. These pulses are arranged so that they impact pellets of tritium-deuterium simultaneously from all directions. This is in the hope that the impacts will induce atomic fusion at which point, it is theorized, the reaction will produce more output than produced by the lasers. So far, researchers have not been able to achieve “breakeven”, but research is ongoing.
Photochemistry: This is very useful in biochemistry, where it is used to analyze protein folding and function. Some laser systems can produce extremely brief pulses of light – as short as picoseconds (10−12) or femtoseconds (10−15 seconds) to initiate and analyze chemical reactions. The short pulses can be used to probe reactions at a very high resolution, allowing the detection of short-lived intermediary molecules.
Space Exploration: Lasers are useful in space exploration such as aboard the spectrometers in the ESA Cassini probe (Saturn) (Source: esa.int/Our_Activities/Space_Science/Cassini-Huygens/Cassini_instruments).
Spectroscopy: The purity of laser light can be improved upon more than the purity of any other light source, which makes techniques such as Raman spectroscopy possible. Raman spectroscopy, commonly used in chemistry, relies on inelastic scattering of laser light in the visible, near infrared, or near ultraviolet range. The beam interacts with molecular vibrations, phonons (a collective excitation in a periodic, elastic arrangement of atoms or molecules in condensed matter, such as solids and some liquids, often referred to as quasiparticles) or other excitations, resulting in the energy of the laser photons being shifted up or down. This shift provides researchers with a fingerprint by which organic and inorganic molecules can be identified and studied.