Hole-y Quantum Computers a PossibilityCategory: Science & Technology
Posted: February 28, 2013 12:06PM
Among the most important laws of the Universe are the laws of conservation which keep it balanced. One of these laws concerns electric charge and it implies that electric charge can neither be created nor destroyed, though it can be neutralized, such as in an atom. That means that whenever a negative electron is pulled from an atom it must leave a positive hole in its place and now researchers at the University of Pittsburgh and Delft University of Technology are working to take advantage of that for quantum computers.
To many people a hole would just be an empty space and be in no way special, but within quantum mechanics holes do have intrinsic properties, including a spin state. The spin state of a particle gives it a magnetic field with positive and negative poles and can be used to store information. Within a quantum computer the spin of a particle would be put into a superposition, so the particle would exist with multiple spin states at once, giving the computer tremendous computing power. Typically if an electron is used like this, magnetic fields must be used to affect it, but a hole's spin can be manipulated with an electric field.
The spin state of a hole is also less influenced by the nucleus of an atom, allowing it to persist for up to 10 times longer. That longer life should make this approach very desirable to those developing quantum computers as it will simplify some of the design and potentially increase its computational power.
Source: University of Pittsburgh