Device breakthrough would aid quantum computer development
Researchers have proven a theoretical technique to make a simulator for subatomic particle behaviour, which could one day lead to computers billions of times faster than today's machines.
In a study published in the journal Nature Physics, researchers at the Imperial College London found that their device would be able to duplicate a so-called quantum system. Such a system would be governed by the rules of quantum physics, as opposed to classical physics laws such as mechanics, gravity and Einstein's theory of relativity. Quantum mechanics govern particle interactions below the atomic scale, where conventional rules of physics break down.
The technique could eventually help scientists develop quantum computers — machines whose calculations are performed through these subatomic interactions — that would be astronomically faster than anything that exists today.
"I would say it is a significant step toward these devices," Michael Hartmann, the study's leader, told CBC News Online in an e-mail message Monday.
Hartmann's discovery with colleagues Fernando Brandao and Martin Plenio suggests scientists would be able to control individual particles, a key development.
An entangled state
The study suggests that it is possible to create a condition in a quantum system known as an entangled state, which could be accurately measured. The team's technique would make it possible to accurately measure the system's status, producing information, or a computation. This was previously not possible through established techniques.
The simulator would consist of atoms and photons — light particles — housed in silicon containers about 50 micrometres in diameter, about the width of a human hair. The containers, called toroidal microcavities for their ring-like shape and size, "can store light for a very long time," Hartmann said.
By connecting the cavities with an optical fibre —strands of glass that can carry light like wires carry electricity —the photons could be made to interact with atoms housed in each cavity, he said.
"All these three parts have already been done individually in experiments but not yet been put together," Hartmann said.
The researchers did not construct the device themselves because they lack the technical experience and expertise, but it is something the team is working on.
"We are in discussions with some experimental experts with the aim of doing the experiment," Hartmann said.
"In the very long run, we anticipate that these kinds of simulators could potentially be used to create new materials with capabilities and characteristics which do not occur naturally," Plenio said in a written statement.