The emergence of spontaneous quantum chaos in atomically thin layers of insulating material has baffled scientists, necessitating model changes that have the potential to resolve several urgent issues in the understanding of superconductivity.
Experimental physicists from the National Institute for Materials Science in Japan and Princeton University in the United States studied the emergence of spontaneous quantum fluctuations at a two-dimensional landscape transition from electron traffic jam to the superconducting expressway.
Senior author and Princeton physicist Sanfeng Wu says, “This is an exciting field of study: how a superconducting phase can be changed to another phase.”
“And we have been interested in this problem in atomically thin, clean, and single crystalline materials for a while.”
It’s difficult for the electrons cruising through the copper wiring under your walls to get from point A to point B. When you turn on the screen, you’ll see electrons swerving, bumping, tooting their tiny electron horns, and shaking their small electron fists as their tiny electron engines overheat. It’s peak-hour madness.
In theory, superconductivity is ideal. It moves smoothly from beginning to end. No heat, no energy lost. It’s as efficient as it gets, making it ideal for producing strong electromagnetic fields or high-performance computing that doesn’t overheat.
However, producing this phase of conductivity is likewise not a straightforward task. The process happens when electrons shed their individuality and synchronize to create Cooper pairs, which are able to navigate the atomic neighborhood with a Zen-like ease.
This calls for a degree of coolness that can only be attained with some really amazing, powerful gear. However, scientists might be able to get away with a bit less cooling if they could figure out exactly what causes this quantum transition and the part that temperature plays in it.
Studying the quantum behavior of electrons trapped on effectively two-dimensional surfaces is one field of inquiry. Quantum phenomena find it more difficult to shift into a superconductive state when they are deprived of their ability to move up and down.
According to Princeton physicist Nai Phuan Ong, “As you go to lower dimensions, fluctuations become so strong that they ‘kill’ any possibility of superconductivity.”
The easiest way to characterize the principal destroyer of the electron’s zen state is as a quantum vortex. Stated differently, Ong refers to them as “quantum versions of the eddy seen when you drain a bathtub.”
As per the BKT transition, named for Nobel laureates Vadim Berezinskii, John Kosterlitz, and David Thouless, these deadly vortices of doom disappear in 2D materials at sufficiently low temperatures.
Wu and his colleagues created a single sheet of semi-metal tungsten ditelluride to investigate this realm of quantum tornadoes wreaking havoc with superconductive states. At temperatures even slightly over absolute zero, ditelluride acts as an energy-stifling insulator.
However, we discovered that the minute the critical electron density is crossed, the vortex signals suddenly’ disappear. This was shocking as well. This observation—the sudden end of the fluctuations—defies every explanation.”
Novel models open up new research directions that might result in novel technologies. With the potential benefits of achieving room-temperature superconductivity, a comprehensive understanding of the quantum landscape’s meteorological conditions is beneficial.
