A quantum computer, which could process information much faster than today's systems, may be one step closer.
Researchers from Harvard University and MIT and the Max Planck Institute of Quantum Optics in Germany have recently made a breakthrough in quantum computing.
Computers use electronic versions of binary switches to perform calculations in order to perform functions. These carry out the mathematics needed for operation.
At the smallest scales, subatomic particles exhibit a characteristic called spin. Although it is not a physical spin, the particles have effects similar to a spinning magnetic field, giving the phenomenon its name. This spin can be read either as a 0, 1 or, oddly, as superposition of the two spin states, called a quantum bit or qubit.
A quantum computer able to manage and read these spin states would be able to perform calculations at tremendous speeds. This could lead to new generations of computers. Calculations impossible using the world's largest supercomputers would be within the capabilities of quantum computers. Extensive climate models and drug behavior could be calculated using the theoretical machines.
Researchers from the Massachusetts Institute of Technology and Harvard University found a novel way to connect an atom to a single photon of light.
A single atom of the metal rubidium was coupled to a photon of light. By using a switching mechanism, the researchers where able to control the behavior of the photon by affecting the coupled atom. Effects could also be produced on the atom by altering the photon. This two-way control could provide the basis for quantum computing. Development of the technique could lead to multiple processes taking place in an extremely small area.
"This is a major advance of this system. We have demonstrated basically an atom can switch the phase of a photon. And the photon can switch the phase of an atom," Vladan Vuletić from MIT, and co-author of the paper announcing the breakthrough, said.
The strange qubit state is extremely fragile, providing challenges to quantum computing. Traditional devices needed to be kept extremely cold, requiring large mechanisms to maintain. Placing several qubits in close proximity can cause them to collapse into a more stable spin state. The new technology could provide a way of stabilizing quantum processors.
"We expect our experiment to enable various applications," Max Planck Institute researchers wrote in the article detailing their investigation into quantum gates, including scalable quantum computation and quantum communication.
A pair of articles from the two teams of researchers were published in the journal Nature.
