It uses ions that exist in two states at the same time

Jan 20, 2015 08:27 GMT  ·  By
Entanglement system being created by Postdoctoral Fellow Dr Seb Weidt, PhD students Kim Lake and Joe Randall
   Entanglement system being created by Postdoctoral Fellow Dr Seb Weidt, PhD students Kim Lake and Joe Randall

Quantum computers are considered the next big leap in technology, provided we can actually make them happen. According to physicists at the University of Sussex, we already have the means: microwave radiation and Schrӧdinger's Cat.

“Schrӧdinger's Cat” is an experiment which requires that one put a cat inside a bunker with a barrel of gunpowder or a batch of poisonous gas that has a 50-50 chance of setting off in the next minute. Well, in theory.

While the experiment is happening, we can't know if the cat is dead or alive until we look inside the bunker (or box, or whatever).

The quantum mechanical interpretation of the experiment is that until we look in the box, the cat exists in a state of superposition, being both dead and alive, meaning that our active looking forces nature to decide on one of the two.

Sussex physicists got their new study published this week in Physical Review. It describes how they managed to use trapped ions (charged atoms) as Schrӧdinger's Cat in their quest to create a quantum computer.

The ions exist in two states at the same time, each storing a qubit, while creating an “entanglement” effect which can transfer information through the collective quantized motion of the ions in the trap. The scientific explanation is a lot more involved and complicated, but suffice it to say that trapped ions challenge the fabric of reality as we know it.

The new trapped ion supercomputer is based on microwaves

This is the big change in approach that the Sussex researchers came up with in order to make quantum computing a viable prospect.

Normally, quantum processes are driven by lasers, but it would take millions of table beams carefully aligned in order to process a large enough number of ions to encode data.

The Sussex team determined that microwave radiation would be much better, as it can easily broadcast over a large area and the technology for it is already well developed and stable.

Their Schrӧdinger's Cat ions were successfully controlled in this manner, which they believe finally makes quantum computers a feasible endeavor. Alas, it will probably take a long time for any practical applications, years or decades maybe.

“While constructing a large scale quantum computer is still a significant challenge, this achievement demonstrates that we are moving beyond basic science towards realizing new step-changing technologies that have the potential to change our lives,” said Sussex team leader Dr. Winfried Hensinger.