Researchers at Chalmers University of Technology in Sweden completed a trial in which they were able to extend the average life of an artificial atom tenfold by placing it in front of a mirror, and then adjusting the distance between the two.
The life of the atom is defined as the amount of time it takesfor energy that has been added to the atom to dissipate, returning the atom to its prior state.
The faux atom is a superconducting electrical circuit which the researchers are able to charge with energy, or “excite,” just like they would do with an actual atom. Since the researchers possessed great control over the way the circuit acted, the artificial atom gave off the energy via light particles just like an actual atom. However, the light given off by the mock atom possessed less frequency, essentially making the particles microwaves.
Per Delsing, a professor of physics at Chalmers who led the research group said, the display proved that the lifetime of an atom can be adjusted in “a very simple way.”
“If we place the atom at a certain distance from the mirror the atom’s lifetime is extended by such a length that we are not even able to observe the atom,” Delsing added. “Consequently, we can hide the atom in front of a mirror.”
The concept of improving the lifetime of an atom by altering the distance between it and the mirror was developed by theoretical physicists, who worked along with experimental physicists on the testing.
“The reason why the atom “dies”, that is it returns to its original ground state, is that it sees the very small variations in the electromagnetic field which must exist due to quantum theory, known as vacuum fluctuations,” said Göran Johansson, a professor of Theoretical and Applied Quantum Physics who led the group of theoretical physicists.
When in front of the mirror, the atom associates with its own reflection, an action that alters the vacuum fluctuations that the atom interacts with. So, by successfully completing the experiment, the researchers were able to demonstrate a scheme that could be used to measure the fluctuations.
The experiment and its related results can be read for a fee in the Nature Physics journal article “Probing the quantum vacuum with an artificial atom in front of a mirror.”