Cyclops, a superhero from the famous comics “X men” has been the favorite of many people across the world. In the story, the character produces powerful laser beams by optical blast from his eyes.
This fiction has become a reality by the joint efforts of Seok-Hyun Yun and Malte Gather, two physicists at Massachusetts General Hospital.
They were able to develop a technique by which laser can be produced from human cells. The device used to produce this laser consists of the same components that are used to produce a real time laser. That is, a pump source, an optical cavity and a gain medium. The pump source is used to produce the initial energy, the optical cavity to concentrate the energy, and the gain medium is a substance in which the electrons are exited until they go from a lower energy level to a higher energy level.
The researchers began experimenting on human kidney cells to produce green florescent proteins (GFP). This substance is known to produce luminance in jellyfish. Many steps were carried out to produce the laser. They began by placing the modified cell between two mirrors there by creating an optical cavity (a cell sandwich as called by researchers). Then a blue light pulse was passed through the cell and the light bounced between the mirrors, causing the cell to glow. When the cell was observed through a microscope, they saw that the cell was glowing with a spot of laser.
Researchers suggest that this laser is suitable for many medical applications. For the diagnosis of diseases, nowadays a laser beam is passed into the body to get images or to attack the disease causing cells. There might also be a time when the human cells can be illuminated as laser. The illuminated cells can gather more information about the interior of the human body by penetrating the damaged tissues more deeply. More research has to be done to realize this as laser needs an external light source to illuminate.
Some say that this technology will be more useful in gaining information about individual cell characteristics than medical applications as the laser needs an external light source and it is difficult to produce it inside human body. Yen suggests that by integrating a nano scale cavity to laser cell we can produce a cell that will illuminate itself without any external source. Let’s hope that this technology will come into reality in the near future itself – who doesn’t want to shoot a laser from our own body.
A team of researchers at the Massachusetts Institute of Technology (MIT) has invented a new way of shrinking circuit structures in semiconductors, which is certainly an advancement of the Moore's law. Moore’s law is the standard that defines the growth in semiconductors. The law named after Intel co-founder, Gordon E Moore, states that the number of components in integrated circuits had doubled every year from the invention of the integrated circuit in 1958 until 1965. His prediction proved to be accurate and the law is still practised in the semiconductor industry for long-term planning and to set targets for research and development, said a report.The chip manufacturing industry resorts to photolithography techniques, which means producing chip features that are larger than the wavelength of the light applied. MIT researchers have developed a new process that can create complex chip structures, which would be 1/8th the size of the wavelength of the light used. It is a process that is described in the paper as "Breaking the Far-Field Diffraction Limit in Optical Nanopatterning via Repeated Photochemical and Electrochemical Transitions in Photochromic Molecules", published in Physical Review Letters.
The researchers term it as an effect called Stimulated Emission Depletion imaging (STED), which enabled them to go beyond the current limitations of photolithography. Scientists make use of the fluorescent characteristics of materials to emit light when targeted by a laser beam in STED. The power of light emitted can be controlled by the intensity of the laser beam. If the power falls enough, it causes a 'dark patch' that is smaller than the wavelength of the laser light itself. These dark patches can be used as masks, which can be applied to a surface, said a Toms Hardware report.The MIT Researchers opine that this invention can help in constructing semiconductors with much finer structures than what is possible today. MIT said that there could also be an opportunity to apply this technology in photonic devices.
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