Perfecting Cryogenic Systems for the Quantum Computer Market

Cool technology enables quantum computing

Excerpts and salient points ~

+  Researchers attempting to build the next generation of quantum computers are pushing the boundaries of what can be achieved with current experimental technologies. One of the challenges is testing the behaviour of a complex quantum system when it is sealed inside a cryogenic system cooled close to absolute zero. Not only does it make it difficult to assemble, adjust and maintain the components and wiring needed for each experiment, but it can also place practical limits on the size of the quantum system that can be measured.

“Many new technologies, including quantum computing, require a controlled measurement environment at temperatures close to absolute zero,” says David Gunnarsson, the company’s chief sales officer. “Cryogenic systems have traditionally been difficult to use and maintain, and our aim is to eliminate those obstacles and enable our users to focus on being creative in their research.”

+  The latest addition to Bluefors’ modular system is the option for high-density wiring, which has become increasingly important as scientists seek to increase the number of qubits in their quantum computing systems. “Until now it has been necessary to attach each component one wire at a time, which is fine for small-scale systems,” says Gunnarsson. “But the footprint of the cryogenic system gets used up quickly as more quantum elements are added, and assembly, installation and maintenance become much more difficult and time-consuming for large numbers of wires and components.”

+  Gunnarsson explains that most experiments in cryogenic systems require several continuous control wires from room temperature down to the lowest temperature in the cryostat. Typically, two or three wires might be needed to control and measure each quantum element – depending on the experimental architecture that has been deployed. The challenge for researchers is how to scale up from lab-scale demonstrations with just a few qubits to more useful quantum computers that will need hundreds of quantum elements.

+  To address this need, the high-density interface introduced by Bluefors allows researchers to build experiments with more than 1000 high-frequency lines in one system. Making sure that each wire is connected properly is more difficult with such a large number of control lines, so the interface has been designed to allow the wires to be installed in blocks of 12.

+  The interface exploits standard connectors and coaxial cables for the wiring, and the attenuators have been embedded in a single block that fits into the modular system. Meanwhile, the modular form factor also allows the use of custom components with multiple high-density channels, such as amplifiers, filters and attenuators.

+  Further into the future, quantum computers are likely to need millions of qubits. It would be impossible to connect that many cables into a cryogenic system, and Gunnarsson says that the research community is still working to develop new technical solutions, such as cold logic and wire multiplexing. “Bluefors is active here and the modular concept will support these developments,” he says.

Source:  physicsworld.  Bluefors,  Cool technology enables quantum computing…

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