Microsoft’s Quantum Chip Helps Control Thousands of Qubits
Microsoft not only makes Windows and Surface tablets, but also does interesting work with quantum computers. And, according to the Redmond, Washington-based company, at least, that’s just a remarkable advance in this area.
In collaboration with researchers from the University of Sydney in Australia, Microsoft researchers have found a way to control thousands of qubits, the basic units of quantum information that correspond to binary bits in a classic computer, at extremely low temperatures.
This is important because one of the major challenges in quantum computers that can change the face of the computer as we know it is what is known as qubit decoherence. This is the cause of many errors in quantum computing and results from the environment’s interaction with qubits in a way that changes their quantum states.
“Each qubit must be controlled by a series of wires that normally run from room temperature electronics racks to the qubits at the end of a dilution refrigerator at 0.01 degrees Kelvin. [which is] close to absolute zero, ”David Reilly, principal researcher and director of Microsoft Quantum Sydney, told Digital Trends. “If you control qubits this way, you get about 50 qubits. It just doesn’t scale as an approach to controlling thousands of qubits and beyond. Routing wires from electronics racks is more like the first electronic computers in the 1940s than the integrated circuit chips we have today. “
The researchers developed an innovative solution to this problem. It consists of a control chip they call Gooseberry, which enables the control system to be scaled and reduces the bottleneck of control lines and signals that would otherwise be present. The control chip consumes little electricity. This means that the qubits themselves are not heated.
“The chip is the most complex electronic system that can operate at this temperature,” explained Reilly. “This is the first time that a mixed-signal chip with 100,000 transistors is operated at 0.1 Kelvin. [the equivalent to] -459.49 degrees Fahrenheit or -273.05 degrees Celsius. “
Reilly said this work represents a “big step” for quantum technology, although “more leaps” must be made before a truly useful quantum computer can be developed. If it does, however, then hopefully all of the research and development effort that has got to this point will be more than worth it.
An article was recently published in Nature magazine entitled A Cryogenic Interface for Controlling Many Qubits.