Australian engineers design silicon-based quantum chip
Fri 15 Dec 2017

Engineers at the University of New South Wales (UNSW) have unveiled a new design for a silicon-based quantum computer processor. The design is built on existing semiconductor technology, with innovative architecture that allows for quantum calculations.
The new chip design could represent a giant step forward in the quantum computing arena; not in the least because it can be manufactured in an existing semiconductor facility, as the design is based on complementary metal-oxide semiconductor (CMOS) technology – the basis for all modern semiconductor chips.
The silicon-based quantum chip incorporates a transistor-based control circuit with charge-storage electrodes. When the electrodes above a qubit are selected and controlled using a microwave cavity, the spin is controlled, reflecting a 0/1 quantum binary code. The resulting system of regulated, interactive qubit spin can be dense, with several chips integrated to a single system, and scalable, providing for extremely large calculations.
Dr. Menno Veldhorst, lead author of the paper introducing the quantum chip, said that the new design is aimed at packing qubits together and integrating them, like microprocessor chips, so that an enormous amount of computing power can be directed at solving important, complex problems such as cancer or climate change research.
“Our design incorporates conventional silicon transistor switches to ‘turn on’ operations between qubits in a vast two-dimensional array, using a grid-based ‘word’ and ‘bit’ select protocol similar to that used to select bits in a conventional computer memory chip,” Dr. Veldhorst said.
“By selecting electrodes above a qubit, we can control a qubit’s spin, which stores the quantum binary code of a 0 or 1. And by selecting electrodes between the qubits, two-qubit logic interactions, or calculations, can be performed between qubits.”
Andrew Dzurak, Director of the Australian National Fabrication Facility at UNSW and one of the designers of the chip said that while many people consider the moon landing to be humanity’s greatest technological marvel, the advancements made in the field of microprocessors are an outstanding achievement, that has “revolutionized modern life.”
He added, “With quantum computing, we are on the verge of another technological leap that could be as deep and transformative.”
Earlier this week, some of the largest global corporations made strides in exploring quantum computing, with Microsoft releasing tools for developers of quantum applications, and IBM recruiting partners including universities, finance, and technology companies to test its 20-qubit quantum system.