Researchers from Microsoft and the University of Sydney in Australia are currently working on developing their own quantum computing system that uses CMOS-based silicon chips.
Complementary metal-oxide-semiconductor (CMOS) technology is already used to create a number of different computer components and for this reason, scientists developing quantum computers are trying to use this familiar approach instead of liquid-state nuclear-magnetic-resonance or ion traps.
While the notion of a silicon-based quantum computer was first put forth by researcher Bruce Kane back in 1998 in a paper, scientists are just now coming up ways to turn his idea into a reality. One of the biggest hurdles they’ve had to overcome is the fact that CMOS components generally put off more heat and interfere with quantum bits or qubits.
Keeping qubits cool requires them to be refrigerated at near-zero Kelvin temperatures which is why the quantum computers developed by IBM and Honeywell currently have lower qubit counts. To build a quantum computer with hundreds to thousands of qubits, this problem will need to be solved and it appears that Microsoft is on its way to coming up with a solution.
Gooseberry
Researchers from Microsoft and the University of Sydney recently published a paper in Nature Electronics detailing how they’ve developed a chip that can support thousands of qubits called Gooseberry.
General manager of quantum hardware at Microsoft Chetan Nayak explained in a blog post how the team headed by Dr. David Reilly has devised a way to overcome quantum computing’s cooling problem, saying:
“The chip powering this platform, called Gooseberry, resolves several issues with I/O in quantum computers by operating at 100 milliKelvin (mK) while dissipating sufficiently low power so that it does not exceed the cooling power of a standard commercially-available research refrigerator at these temperatures. This sidesteps the otherwise insurmountable challenge of running thousands of wires into a fridge.”
At the same time, the researchers have also come up with a cryo-compute core that sits above Gooseberry in the quantum stack in order to relay information from the quantum layer. This core is a general-purpose CPU that has been designed to operate at a higher temperature of 2 K as opposed to 100 mK.
Both Gooseberry and its cryo-compute core are still in the development stage but we’ll likely hear more from Microsoft once the company actually begins making them.
Via The Register