Building quantum technologies is the definition of finicky. And there is one primary reason: the fundamental unit of information is not a bit, but a qubit. Though qubits come in many guises – trapped ions, neutral atoms, superconducting circuits, particles of light, etc – they all share three quantum properties.
First, a qubit does not just represent a 1 or a 0, but can exist in a superposition of states, an uncertain blend of both until it collapses to a 0 or 1 when measured. Second, a qubit can be entangled with other qubits, meaning their physical states become entwined regardless of their distance from one another. And third, all qubits are extremely fragile or, in technical terms, they are vulnerable to decoherence.
Whereas the first two properties offer the potential to provide huge advantages for quantum technologies over their classical counterparts, the latter has been a stumbling block for decades. Qubits lose their quantum properties with almost any interaction with the environment, meaning any mote of dust, tiny vibration or stray photon has the potential to scupper a quantum process.
Filling the vacuum
Vacuum and cryogenic environments play an essential role in mitigating decoherence across many major quantum modalities, whether this is superconducting, trapped, neutral atom or photonic, and these technologies are coming out of the laboratory into the real world.
For example, whether operating a trapped-ion quantum computer or an advanced quantum gravimeter, if left unmitigated, qubits are bombarded by trillions of gas molecules every second, immediately causing them to decohere. Extreme-high vacuum (XHV) environments eliminate this problem, effectively removing ambient matter from the equation.
Vacuum technologies are also needed in concert with cryogenics in low-temperature dilution refrigerators that prevent heat causing decoherence in superconducting quantum computers and ultra-sensitive single-photon detectors used in quantum communication. These refrigerators cool hardware down to sub-Kelvin temperatures (~10 mK) – hundreds of times colder than deep space.
“We have shipped products that support XHV environments, 10-12 millibar, to isolate everything from the environment of the hardware. We also have plans in our roadmap to go beyond the current pressures, and we have worked with companies that build these dilution refrigerators,” says Jos Donders, head of the Emerging Markets & Technologies team of Atlas Copco’s Scientific Vacuum Division.
“What is very good for us is that 95% of these modalities – whether it’s quantum computing, sensing or communications – require a vacuum and a cryogenic low-temperature environment.”
Going in blind
For Donders, and indeed the global Atlas Copco Group (through the Edwards Vacuum brand), now is the ideal time to be working in quantum across the different modalities. Quantum is still far from delivering on its potential, and there remains significant work to be done in terms of hardware and equipment development to go from the laboratory prototypes of today to the robust machines needed to build useful commercial quantum computers.
For this, scaling the hardware will be essential for companies to enable their goals towards a fully fault-tolerant quantum system solution. As part of the Atlas Copco Group, Edwards Vacuum can offer highly skilled technology and engineering expertise to enable the development of these solutions.
“We are working on solutions for the future,” underlines Donders. By this, he means that most of the time Edwards Vacuum is building vacuum and cryogenic equipment for different quantum modalities that do not yet exist. For instance, when a dilution refrigerator manufacturer or a quantum hardware OEM designs a next-generation platform, Donders and his team discuss in depth future needs with in-house technology engineers to define future solutions based on market inputs from customers in this field. “We sit down, have a detailed discussion, and outline what is possible, what is maybe possible and what is not possible in the timelines that are required,” he says.
A prime example of this in action is Edwards Vacuum’s partnership with Universal Quantum, a UK-based quantum computing company aiming to build robust, scalable quantum computers. In the first act of their ongoing cooperation, in 2022, Edwards Vacuum deeply collaborated with Universal Quantum researchers to deliver an XHV system to house a quantum error corrected quantum computer based on trapped-ion technology that Universal Quantum had not yet constructed.
Roadmap to success
A large part of why it is possible to engineer complex vacuum and cryogenic technologies for quantum computing, sensing and communication devices that do not yet exist is the detailed roadmaps that the major quantum companies produce.
Donders says that these roadmaps are generally not full of blue-sky wishful thinking, but detailed specifications that target specific numbers of qubits, fidelity and also operational parameters by ambitious but realistic dates where timescales matter due to the financial investments behind them.
“At the same time, we also realize that there will be quite some disruptive changes along the way,” Donders adds. “That’s why we work very closely with these companies to synchronize with them and ensure that whatever we develop is in line with their requirements.”
Flexibility and deep technical collaboration are paramount for another reason too: no single quantum modality has yet emerged as the definitive winner. Backed by the scale and industrial expertise of the Atlas Copco Group, Edwards Vacuum works directly with quantum companies, serving as a foundational link in the global quantum supply chain. This means Edwards Vacuum is equally adept at providing ultra-clean XHV systems for trapped ion quantum computing and neutral-atom quantum sensing, specialized helium pumping and circulation setups for dilution refrigerators or robust pumps for quantum key distribution nodes.
As the quantum industry shifts focus from proving basic quantum principles to scaling robust, fault-tolerant architectures, vacuum and cryogenic technologies will remain indispensable. By stepping into the unknown alongside quantum pioneers, Edwards Vacuum is helping lay the physical foundations required to make the quantum revolution a commercial reality. As Donders neatly summarizes: “That’s where we want to be – at the forefront.”
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