Scientists have successfully created an ultra-cold refrigerator that could enhance the performance of quantum computers.
Quantum bits, which serve as the basic elements of quantum computers, need to be maintained near absolute zero temperatures to operate accurately without errors.
Researchers from Chalmers University of Technology in Sweden and the University of Maryland in the US have created a novel cooling technique that could help unlock the complete capabilities of quantum computing.
The cooling systems employed nowadays, known as dilution refrigerators, lower the temperature of the qubits to approximately 50 millikelvins above absolute zero, as stated by the Chalmers University of Technology.
During an experiment, a novel quantum refrigerator cooled the qubits down to 22 millikelvins, which is a temperature 10,000 times lower than normal room temperature, as reported by the research team.
As you approach absolute zero, or 0 Kelvin—which equals -273.15 degrees Celsius—the reliability of quantum computations improves significantly.
However, achieving absolute zero becomes more difficult as the temperature decreases.
Fridge is ‘fully autonomous’
“Temperature essentially refers to the physical phenomenon of atomic vibrations. Imagine cooling an object whose atoms vibrate intensely until they move slower and slower, eventually reaching their least possible motion under quantum mechanical principles. This point of minimal movement is known as absolute zero,” explained Simone Gasparinetti, an associate professor at Chalmers University of Technology and principal investigator for the research, in an interview with LIFEHACKNext.
The team succeeded in reducing these vibrations to one ten-thousandth of their original size, which they claimed was a “record low” for the specific molds.
In contrast to dilution refrigerator systems that demand ongoing external management, this quantum refrigerator functions autonomously after setup.
The refrigerator uses three qubits and operates based on a system where warm and cold environments interact in a specific way to remove heat from a target qubit, the part of the quantum computer that needs to be cooled.
“Energy from the thermal environment, channeled through one of the quantum refrigerator’s two qubits, pumps heat from the target qubit into the quantum refrigerator’s second qubit, which is cold,” Nicole Yunger Halpern, an assistant professor of physics at the University of Maryland, said in a statement.
“That cold qubit is thermalised to a cold environment, into which the target qubit’s heat is ultimately dumped”.
Gasparinetti added: “The refrigerator is fully autonomous, which means, essentially, it only requires coupling to a hot and cold source to function. This is something that is in contrast to other techniques that would require, for example, precisely timed pulses or other forms of control”.
“In essence, you turn it on, and the qubits cool down; after that, you can power it off and begin your calculation,” he explained.
Translating thermodynamics from concepts to applications
According to experts, quantum thermodynamics, a discipline that merges quantum physics with thermodynamics, remains predominantly theoretical up until now.
“Over the past five decades, we’ve downsized numerous components, particularly, though not exclusively, those that are electric,” Gasparinetti stated.
He mentioned, ‘We genuinely wanted to create a practical quantum machine, one that operates based on thermodynamics.’
Scientists claim that this fridge enables qubits to function with significantly reduced error rates and for extended durations in quantum computers.
The team succeeded in decreasing the error rate of quantum computing by twenty times, bringing it down from an initial rate of 0.02 to 0.01.
This might appear minor, yet experts assert that reducing mistakes is crucial for ensuring accurate computations in quantum computing.
Additional efforts are required.
Quantum computers could transform essential technologies across different areas of society, offering uses in fields like healthcare, energy, cryptography, artificial intelligence, and supply chain management.
Nonetheless, researchers indicate that additional efforts are required for quantum computers to tackle complex issues effectively.
“These machines have to get better at many things before they are useful. And we also have to get better at finding ways to use these resources that we have. We have still not fully understood how to harness quantum resources to make useful computations and solve useful problems,” Gasparinetti said.
Gasparinetti also says there’s a widespread misconception that quantum computers will replace classical computers like our laptops.
This technology aims to augment traditional computers so they can tackle highly specialized tasks like logistics optimization or pharmaceutical research. He noted that we would still require conventional machines to run a quantum computer.
“Experiments like the one we did actually show that you can have more functionality very close to the quantum components, which I think is a trend that we will see more of in the future,” Gasparinetti said.
Researchers hope more quantum autonomous machines can be developed.
What other issues might be resolved independently then?
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