## Sunday, June 17, 2012

### Splitting atoms by using quantum mechanics

The concept of an atom has been used by scientists since the ancient Greeks. While the word is derived from the Greek word for indivisible, we now know that atoms are made up of even smaller building blocks. Researchers have managed to split atoms and create enormous amounts of energy, according to the famous law E=MC². This process, called nuclear fission, is based on radioactivity, and works with expulsion of small particles from the atom core. New attempts from the University of Bonn use the fuzzy mechanics of quantum theory in order to split atoms.

Superposition
One of the most basic principles of quantum mechanics is the concept of superposition. It means that small particles can exist in more than one state at the same time. Most well-known is the wave-particle duality, that describes that sub-atomic particles, or even bigger pieces of matter, behave both like waves and particles at the same time. Peculiar enough, once we start measuring the actual properties of these things, they attain the characteristics of either wave or particle and lose their so-called superposition.

Mechanism
Superposition means we are also unable to precisely determine a particle's location, and it also means it can be in more than one location at the same time, but only until we measure it. The Bonn scientists use this quantum mechanical concept to split atoms, by using lasers. Superposition also applies to the spin of atoms, which can be left or right, or both at the same time. Using complex beams of laser light that interact with the spin, an atom can split by moving its spin to the left and right at the same time. As long as it keeps its spin in both directions at the same time, its superposition holds and makes the atom exist with two split halves while still being whole.

Implications
According to the scientists, it is not possible to view the split atom directly. Once you measure it, the splitting process collapses and the atom returns back to its ordinary state of existence. Still, it is possible to prove the two halves have been split once the particle is whole again. The splitting concept can be used to make 'bridges' out of atoms. By splitting a particle, both halves can interact with their neighbours. This is useful for studying various quantum mechanical processes in nature that rely on these fuzzy ways of interaction, which are, among others, found in photosynthesis and electrical circuits.

Outlook
The concept of splitting atoms by using quantum-mechanical superposition is a first step in order to use them as a model to study processes. While being able to control splitting an atom is promising, more studies are required in order to figure out how they can be hooked into a quantum-mechanical system that can consequently be studied. Nevertheless, it is interesting to see that the weird principles of quantum theory can be used for such spectacular experiments. Previous studies showed quantum mechanics can be used for teleportation of data.