19-12-2009, 09:12 AM
Photonic Computing is digital computing in imitation of conventional electronic computing only using laser light instead of electricity, and holograms instead of silicon computer chips. "Photonic" comes from "photon" which is the smallest unit of light just as an electron is the smallest unit of electricity. "Photon" comes from "photo" as in "Kodak moment!" Uninhibited light travels thousands of times faster than electrons in computer chips; therefore it is capable of computing thousands of times faster than electronic computing. Therefore, light computers will compute thousand of times faster than any electronic computer can ever achieve due to the physical limitation differences between light and electricity.
In a nut shell, the photonic transistor products, which are expected to replace much of the electronics infrastructure during the 21st century, can be made smaller, faster, and cheaper. They are more reliable, generate less heat, and are not susceptible to interference from outside influences. In comparison to photonics, even the best electronics is slow, because photons are faster than electrons. Unlike electronic circuits, photonic circuits process information by manipulating light with light at the speed of light. The amount of information that can be processed in one second depends on how fast the components in the circuit are able to control information.
1. What is Photonic Computing?
With todayâ„¢s growing dependence on computing technology, the need for high performance computers (HPC) has significantly increased. With the help of virtual product design and development, costs can be reduced; hence looking for improved computing capabilities is desirable. Optical computing includes the optical calculation of transforms and optical pattern matching. Emerging technologies also make the optical storage of data a reality.
The speed of computers was achieved by miniaturizing electronic components to a very small micron-size scale, but they are limited not only by the speed of electrons in matter (Einsteinâ„¢s principle that signals cannot propagate faster than the speed of light) but also by the increasing density of interconnections necessary to link the electronic gates on microchips. The optical computer comes as a solution of miniaturization problem. In an optical computer, electrons are replaced by photons, the subatomic bits of electromagnetic radiation that make up light.
Electronic computing uses electrons to perform the logic that makes computing work. Photonic computing uses photons of laser light to do the same job, only thousands of times faster. Electronic transistors are whittled into silicon wafers to make modern computer chips. Today's technology, however, is pushing the electron to its physical limits. As a result, the manufacturing processes are becoming increasingly expensive for producing even minor improvements. However, photons are manipulated using inexpensive computer-generated holograms made of plastic or glass. Photonic computers, therefore, will be far more valuable than their slower electronic counterparts, and far less expensive to manufacture.
Interestingly, most telephone companies have been investing heavily in the global conversion from copper wire to optical fiber because light does a better job of carrying information than does electricity. This is because photons (the basic unit of light) go faster, and have a higher bandwidth than do electrons. Bandwidth refers to the amount of information that can be transmitted simultaneously through a given device. Thus, photons are inherently more valuable than electrons. If we can just get them to accomplish the logic tasks that make computing work, they will become the next logical computing upgrade.
Over 65 major companies have invested heavily in the search for an inexpensive "nonlinear" crystal able to make one light beam turn another light beam on and off, which is a prerequisite for the production of a completely photonic (optical) computer.
Photonic logic, based on a different physical principle, is proving to be the key to the production of a completely optical computing system. Such a system would completely replace the start-and-stop surges of electrons with tiny light beams that simply blink on and off, in order to carry information and perform the logic of computing in light-speed photonic computers... without slowing down the photons in some crystal or enslaving them to some electro-optical process.