Breakthrough in Quantum Computer Race
September 29th, 2010Via: University of New South Wales:
A team led by UNSW engineers and physicists have developed one of the key building blocks needed to make a quantum computer using silicon: a “single electron reader”. Their work has been published in the journal Nature.
Quantum computers promise exponential increases in processing speed over today’s computers through their use of the “spin”, or magnetic orientation, of individual electrons to represent data in their calculations.
In order to employ electron spin, the quantum computer needs both a way of changing the spin state (write) and of measuring that change (read) to form a qubit – the equivalent of the bits in a conventional computer.
In creating the single electron reader, a team of engineers and physicists led by Dr Andrea Morello and Professor Andrew Dzurak, of the School of Electrical Engineering and Telecommunications at UNSW, has for the first time made possible the measurement of the spin of one electron in silicon in a single shot experiment. The team also includes researchers from the University of Melbourne and Aalto University in Finland.
“Our device detects the spin state of a single electron in a single phosphorus atom implanted in a block of silicon. The spin state of the electron controls the flow of electrons in a nearby circuit,” said Dr Morello, the lead author of the paper, Single-shot readout of an electron spin in silicon.
“Until this experiment, no-one had actually measured the spin of a single electron in silicon in a single-shot experiment.”
By using silicon-the foundation material of conventional computers-rather than light or the esoteric materials and approaches being pursued by other researchers, the device opens the way to constructing a simpler quantum computer, scalable and amenable to mass-production.
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Now the team has created a single electron reader, they are working to quickly complete a single electron writer and combine the two. Then they will combine pairs of these devices to create a 2-bit logic gate – the basic processing unit of a quantum computer.
