Added by Erik West on October 19, 2012
Researchers at the US University of Princeton announced on Friday they have developed a method that could make quantum computing feasible at a scale large enough to be applied to problems that take today’s fastest computers years to solve.
“Today’s computers, referred to as classic computers, store information using bits – each bit can have a value of 0 or 1. Quantum computers use the special characteristics of quantum mechanics so that they represent quantum bits, or qubits, which can represent all of the values between 0 and 1 at the same time. It’s a very unusual concept, yet it has big implications for the capability of computers to solve very difficult problems that cannot be solved using today’s computers,” said an analyst.
The finding focuses on measuring a quibit, which are extremely delivate. Quibits are so delicate that the influence of light can destabalize the quibit – leading to errors in the information the quibit represents. The research focuses on measuring a quibit without disturbing it.
The technique uses two branches of science – materials science and optics science. The process involves grouping electrons on a wire so thin that electrons must travel on the wire in single file – electrons move in very large groups within a large stream of electrons in regular wires. Once the electrons are arranged in a certain way on the thin wire, the researchers used microwaves to determine where on the wire the electrons were, which allows the researchers to determine the state of a quibit without disturbing it.
The research works for just one quibit at the moment – a very large number of quibits are necessary to form the basis of a functioning quantum computer.
“A quantum computer’s main trait is it can solve a certain type of problem very quickly because it can approach the solution to the problem in an entirely new way. For example, if password you use for your email is eight letters long, today’s computers would have to make up to about 208 billion -or the number 2 followed by 9 zeros – guesses to find your password. A quantum computer could guess your password with at most 456,000 guesses – that’s 456 followed by just three zeros – a much smaller number of guesses,” explained the analyst.
“The point of a quantum computer is not that they can do what a normal computer can do but faster; that’s not what they are. The quantum computer would allow us to approach problems differently. It would allow us to solve problems that cannot be solved with a normal computer,” said an assistant professor of electrical engineering who is part of the research team, Andrew Houck.
Jason Petta, the research team’s leader, said the next step is to improve the reliability of the method, and then add more quibits. The research team says they are optimistic that their technique will work with a large number of quibits, yet temper their optimism since their method will become more complex with a larger number of quibits.
Richard Feynman, an American theoretical physicist known for his work in quantum mechanics, introduced Quantum computing in 1982, yet the field is still considered to be in its early phase of development.
The primary challenge in developing a practical quantum computer, say scientists, is the loss of a characteristic called coherence as a result of influences from the surrounding environment. Light and magnetism are examples of environmental influences that affect coherence.
The researchers are basing their work on quantum computers that use trapped quantum particles – another type of quantum computer, called a topological quantum computer, is thought to be more stable yet can perform the same functions as a trapped particle quantum computer.
Practical applications for quantum computers include simulations for in the fields of chemistry and nanotechnology – many consider quantum simulation a very important application of quantum computing.
“The team’s research offers a practical means of dealing with a key difficulty in quantum computing – research continues, and we’re starting to see the benefits of that today,” added the analyst.