Under the right circumstances, individual electrons can form partnerships that allow them to seamlessly cleave through special materials called superconductors – leaving them to conduct electricity without resistance.
That in itself is quite impressive. But now physicists have found evidence that these quantum partnerships – known as the "Couples of Cooper" – are also capable of acting as a whole new state of matter.
Collaboration by researchers from China and the United States noticed the strange activity of electrons in an experiment. created to address the longstanding question of whether there is any middle ground between free roaming and locked-in couples.
Traditionally, Cooper pairs were thought to have exactly these two states ̵
It has now been found that these quantum marriages also have a state between – not superconducting current, but neither or blocking it. As something like normal, separate electrons
And while this sounds like a loss of superpowers, this between states is actually like nothing we've seen before. In fact, it attracts attention as a whole new state of matter.
To understand this, we have to go back a little.
Typically, electrons, like any other fermion-type particle, have their own identity embedded in a quantum signature, which means that they can never occupy the same space.
Therefore, two fermions cannot occupy the same. space, while particles called bosons can slide through each other like ghosts. And this is the reason for the resistance when electrons travel through material – they eventually collide with one another and lose energy as they travel.
But in the 1970s, an American physicist by the name of Leon Cooper developed that electrons are the right kind of conducting material to form partnerships with each other at low enough temperatures.
They were called Cooper Couples and the remarkable result of this pairing was the loss of a clear quantum identity, giving them a bosom-like ghostly nature. This helps them slip easily through the lattice of material-forming atoms, creating a superconducting state.
Superconductors are appreciated by engineers for their efficiency in energy transfer, losing little – if anything – as heat. Unfortunately, the practicality of superconductors is quite limited, requiring either extreme cold or extreme pressure to work.
One of the main goals of modern physics is to determine exactly how Cooper pairs work and how we can create them without having to squeeze hard or lower the temperature.
In 2007, a small team of physicists at Brown University in the US discovered that Cooper pairs also have a second state – that it is possible to create material that actually captures these ghostly electronic pairs on small superconducting islands, effectively freezing them in their tracks.
This means Cooper couples can either run full steam forward through a wire or sit relatively still in an insulator.
In a recent experiment, researchers from the same team wanted to make material that allowed Cooper couples to move at a slow pace, just as single electrons could travel through any kind of garden metal at room temperature.
"There was evidence that this metallic state would occur in thin-film superconductors as they were cool. Forward to their superconducting temperature, but whether or not that state includes Cooper pairs is an open question, "says Brown University physicist Jim Vales.
" We have developed a technique that allows us to test this question and show that indeed the Cooper pairs are responsible for transporting the charge in this metallic state. "
The technique focuses on a plate of material similar to the one used in the 2007 experiments on the isolation of the Cooper pair.
A thin strip of superconducting yttrium ba Rhee copper oxide, covered with hexagonal nanoscale arrays (shown below), was exposed to magnetic fields as current passed through it.]
According to their models, the magnetic field must cause the electron flow to flow around the wells. To check whether they were playing solo or as Cooper pairs, the researchers simply had to measure their frequency.
"In this case, we found that the frequency is compatible with the fact that two electrons move at a time, not just one. So we can conclude that the charge carriers in this state are Cooper pairs, not single electrons, "says Vales.
This means it's not like other known metal states where electrons separately run a marathon or sprint. This third state indicates that there are degrees of control for boson-like electrons.
Physicists are yet to elucidate strange behavior, but given that this particular superconductor can operate at a relatively -181 Celsius ( -294 Fahrenheit; better than close Absolute zero!), they should have no problems conducting more experiments.
In addition to the interesting aspects of finding a new state of metals, this may underlie new types of future technologies.
is that they are in a wavy state rather than electrons, so we are talking about them having a phase and interfering in the same way as light, "says Vales.
"So there may be new modalities for moving charge in devices through play with boson interference."
This study was published in Science .