Quantum computers still require large, dedicated rooms and complex installations, but now, in a new step towards bringing the technology out of the lab, researchers have designed a prototype quantum computer that is compact enough to fit in ordinary data center racks.
The prototype is an exciting development in an industry that relies mostly on lab-based implementations, where quantum computers can only be controlled thanks to purpose-built infrastructure. Developing a set-up that is more accessible is, therefore, key to expanding the reach of the technology.
This is why the EU recently launched AQTION, a €10 million project that aims to create a compact ion-trap quantum computer that meets industry standards without needing an ultra-stable lab environment for operation.
"Our quantum computing experiments usually fill 30- to 50-square-meter laboratories," says Thomas Monz, AQTION project coordinator. "We were now looking to fit the technologies developed here in Innsbruck into the smallest possible space while meeting standards commonly used in industry."
The new device, said the research team, shows that quantum computers will soon be ready for use in data centers.
The researchers used ions, which are single-charged atoms, as qubits. Quantum information is encoded in the electronic state of ions, and operations are performed with laser pulses that modify and control the state of the particles.
To fit in a couple of 19-inch racks, every individual building block of AQTION's quantum computer had to be downsized, from the ion trap processor to the vacuum chamber. The biggest challenge, therefore, was to ensure that the device did not compromise on performance – but the researchers are confident that their prototype is already delivering promising results.
Even outside of the controlled environment that can be achieved in a lab, the device was stable enough to operate without interruption from external disturbances, and the physicists were able to individually control and entangle up to 24 ions. Measurements showed that the system's performance and error rate were on par with lab-based implementations.
"We were able to show that compactness does not have to come at the expense of functionality," said Christian Marciniak, researcher at the University of Innsbruck.
By next year, the team is expecting to create a device with up to 50 individually controllable qubits.
For now, however, the prototype's hardware and software capabilities will be further upgraded before it is made available online. Researchers will access the device over the cloud to test quantum algorithms on a hardware-agnostic quantum computing language.