Addy Dugdale at Fast Company has written an article about one of the latest advances toward quantum computing,
Quantum computing just got a little bit closer, after an Australian team of researchers unveiled a seven-atom transistor. Measuring just four billionths of a meter and embedded in a single silicon crystal, it acts as a switch on a chip and paves the way for faster processing in an even smaller package. The team, from the Centre of Quantum Technology at the University of New South Wales, did the tricky stuff by hand, which means that commercial versions of their breakthrough will be at least five years away.
The research is pretty exciting stuff and Dexter Johnson (Nanoclast at the IEEE [Institute of Electrical and Electronics Engineers]) helps put the feat into perspective,
The quantum computer is one of those technologies that gets held out as some sort of Holy Grail and remains just as elusive with those who have claimed to have achieved it being regarded with a high degree of skepticism.
One avenue that has been pursued in realizing a solid-state quantum computer has been the use of quantum dots as the building block.
Quantum dots are a strange phenomenon. Spectrum [an IEEE publication] Editor, Eric Guizzo, described them nicely in the quantum computer application as …
So as not to copy Dexter’s entire post here, let’s just say quantum dots can make the process of calculating much faster. But there are problems with using quantum dots as was noted in my May 12, 2010 posting about research at McGill University,
Dr. Peter Grütter, McGill’s Associate Dean of Research and Graduate Education, Faculty of Science, explains that his research team has developed a cantilever force sensor that enables individual electrons to be removed and added to a quantum dot and the energy involved in the operation to be measured.
Being able to measure the energy at such infinitesimal levels is an important step in being able to develop an eventual replacement for the silicon chip in computers – the next generation of computing. Computers currently work with processors that contain transistors that are either in an on or off position – conductors and semi-conductors – while quantum computing would allow processors to work with multiple states, vastly increasing their speed while reducing their size even more.
One other important feature noted in the research from McGill is that several dots may be piled on top of each other in such a way that there appears to be only one dot. Measuring the energy would allow researchers to recognize that situation. Maybe the folks in Australia and at McGill could work together? Of course that won’t fix everything as Dexter points out after the lead Australian researcher, Michelle Y. Simmonds, notes the importance of her team’s work,
The research, which was initially published in the journal Nature Nanotechnology, marks the first time that it has been possible to dictate the placement and behavior of single atoms within a transistor, according to Simmons.
“We’re basically controlling nature at the atomic scale,” Simmons is quoted as saying. “This is one of the key milestones in building a quantum computer.”
[back to Dexter]
Well, there are issues such as entanglement, the coupling between quibits, to be addressed, but it is a step towards quantum computers.