A team of physicists says they have finally figured out one of the most enduring mysteries of quantum physics: why do strange quantum metals seem to operate outside of the traditional rules of electricity?
The answer, they say, lies in the quantum nature of electrons. If proven correct, the findings could open up exciting new paths to a room-temperature superconductor and other futuristic commercial applications that previously seemed impossible.
One of the Greatest Unsolved Mysteries in Condensed Matter Physics
There is something so odd about strange quantum metals that theorists often refer to them as strange, unusual, or downright flummoxing. It’s a mystery so perplexing and enduring that the press release announcing this latest breakthrough termed their discovery as “a solution to one of the greatest unsolved problems in condensed matter physics.”
The thing that makes strange quantum metals so strange is that they do something normal matter isn’t supposed to do. In short, the electrical resistivity (how efficient they are at conducting electrons) of quantum metals is directly proportional to their temperature, even at extremely low temperatures.
So they may come close to superconductivity, meaning essentially no resistance, when they are extremely cold, but as their temperature heats up, their resistance increases linearly. In fact, by the time they reach normal room temperatures, strange quantum metals that are nearly superconductive or actually superconductive at extremely cold temperatures are actually more resistive than normal metals like gold or copper.
Of course, resistivity has been at the center of the news recently, as claims of an essentially zero-resistance “superconductor” that operates at normal pressures and room temperatures have been made and refuted seemingly daily.
Now, a team of researchers led by Aavishkar Patel of the Flatiron Institute’s Center for Computational Quantum Physics (CCQ) in New York City says they have solved the mystery of strange quantum metals’ increased resistivity compared to normal metals and believe their findings could open up all kinds of interesting possibilities, including a replicable path toward actual superconductivity.
Strange Quantum Metals Are All About the Particle Collisions
In their published work, the researchers focused on two specific properties of quantum metals that should explain their linear resistivity. The first is the fact that electrons flowing through a quantum metal can become “quantum mechanically entangled” with one another. This means that any change in spin to one electron is magically transferred to the other. Albert Einstein termed it spooky action at a distance, and it is at the very heart of quantum mechanics.
The second is the structure of quantum metals, which typically have a patchwork arrangement of atoms rather than a smooth one like normal metals. Separately they may not be enough to account for the resistivity mystery, but Patel says if you add them together, “everything just falls into place.”
“The irregularity of a strange metal’s atomic layout means that the electron entanglements vary depending on where in the material the entanglement took place,” they explain. That variance in entanglement adds an element of randomness to the actual momentum of the electrons as they move through the material and interact with each other.
“Instead of all flowing together, the electrons knock each other around in all directions, resulting in electrical resistance,” they explain. And since the electrons end up slamming into one another more often as temperatures increase, the electrical resistance rises alongside the temperature. The researchers say that this combination of factors had never been considered before, but their analysis shows it could definitely be the answer and a shockingly simple one at that.
“This interplay of entanglement and nonuniformity is a new effect; it hadn’t been considered ever before for any material,” Patel said. “In retrospect, it’s an extremely simple thing. For a long time, people were making this whole story of strange metals unnecessarily complicated, and that was just not the right thing to do.”
How Solving This Mystery Can Affect The Future
Although the latest claims of room temperature superconductors seem to be flailing under closer scrutiny, there is still hope that such material may finally be discovered. Many researchers believe that the unique situations where some quantum metals can become superconductive means they may indeed hold the answer.
The researchers behind this latest study say their work may finally offer a critical tool to those efforts, especially when they hit an engineering resistivity roadblock, thereby opening the door to all kinds of futuristic devices like levitating cars and ultra-efficient electric planes that utilize superconductors.
“There are instances where something wants to go superconducting but doesn’t quite do so because superconductivity is blocked by another competing state,” Patel explains. “One could ask then if the presence of these nonuniformities can destroy these other states that superconductivity competes with and leave the road open for superconductivity.”
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at email@example.com.