14 DAY TRIAL // A team of particle physicists announces the creation of a refrigerator, in a quantum system made up of three individual qubits, or quantum bits.
These are the basic components of such a system, and they all respect the entanglement principle. This basically states that any change affecting one of the qubits will affect the other two immediately.
The researchers who designed and created this particular innovation say that they used nothing more than the basic principles of thermodynamics for the job, adding only a little twist at the end.
“When thermodynamics was first invented, it was applied to big, Steam engine sorts of things,” explains Tony Short.
The expert, who holds an appointment as a physicist at the University of Cambridge in the United Kingdom, was not involved in the new research.
“The fact that you can bring the ideas all the way down to individual quantum systems of tiny dimensions and the same basic ideas still work is quite nice,” he adds, quoted by Science News.
According to a new research paper detailing the findings, which will appear in an upcoming issue of the top-rated scientific journal Physical Review Letters, the quantum refrigerator can cool one of the qubits it contains to nearly absolute zero.
All investigators had to do in order to make the three-qubit system work was make use of the two basic properties of any quantum system – entanglement and superposition.
Two of the qubits, making up the actual refrigerator, were placed in two different heat baths, one of them hot, and the other at room temperature.
The third qubit was the object that needed cooling. The research team that conducted the experiments included experts Noah Linden, Sandu Popescu and Paul Skrzypczyk, who are all based at the University of Bristol, in the UK.
The basic operating principle in the quantum refrigerator is fairly simple – the qubit in the hot bath acts on the second qubit through entanglement, forcing it to extract energy from the third qubit.
This means that the latter is becoming increasingly cooler, so that the system remains in balance. In theory, its temperature can be cooled further if the hot bath is made even hotter.
The new research “opens a totally new avenue for interesting questions, combining thermodynamics and quantum information science in a very original way,” says University of Geneva physicist Nicolas Gisin.