Physicists have finally solved the mystery of the unique behavior of “strange metals” that conduct electricity in an unconventional way. According to physicist Aavishkar Patel, this breakthrough could open the way to the creation of more advanced superconductors for quantum computers.
The strange metals exhibit special properties when an electric current passes through them. At extremely low temperatures, these metals become superconductors, meaning they offer zero resistance to the flow of electrons. In contrast, ordinary metals experience an increase in resistance as the temperature rises.
However, the distinguishing feature of strange metals is their even greater resistance to electron flow at high temperatures, even though they are superconductors at low temperatures. As the temperature of a strange metal increases, it reaches a critical point where the resistance suddenly increases dramatically. After this point, the resistance continues to increase in direct proportion to temperature, forming a straight line on the graph. The study was published in the journal Science
To explain this unconventional behavior, Patel and his colleagues from various US universities suggest using a combination of quantum entanglement and randomness. Quantum entanglement refers to correlations between particles that give them a common identity. In strange metals, pairs of entangled electrons, called Cooper pairs, have wavelike properties that allow them to move more easily through the atomic lattice at low temperatures.
However, the arrangement of atoms in strange metals is also relatively random. As the temperature rises, the uneven distribution of Cooper pairs causes them to flow in different directions, chaotizing their momentum and leading to additional collision resistance.
This interaction between entanglement and inhomogeneity is a new effect that has not previously been considered for any material, Patel says. The simplicity of this explanation calls into question the unnecessarily complex schemes that have previously been proposed to explain the behavior of strange metals.
The mysterious behavior of strange metals was first discovered in ceramic crystals known as cuprates in 1986. Physicists Georg Bednorz and Alex Muller, who synthesized the material, were awarded the Nobel Prize for their discovery. This achievement spurred the search for other materials with similar properties, leading to the creation of various superconducting materials.
However, current superconducting materials only work at ultra-low temperatures, which requires a bulky and expensive infrastructure. This limitation prevents them from being used on a large scale.