Magnesium, a light and reactive chemical element, may hold a major surprise. Researchers are considering giving it a novel role in the field of superconductors.
This alkaline earth metal, abundant in nature and essential to human metabolism, is also produced by aging stars. Although a good electrical conductor, it was never considered a superconductor until recent studies.
A research team including Giovanni Ummarino from the Polytechnic University of Turin has explored how quantum confinement could transform non-superconducting elements into superconductors. Their study, published in
Condensed Matter, suggests magnesium could achieve this state in ultra-thin films.
Quantum confinement, a phenomenon where a quantum particle's energy increases with spatial restriction, is central to this discovery. The researchers' calculations, without adjustable parameters, predict a critical temperature of 10 Kelvin for magnesium films thinner than 1 nanometer.
This temperature, achievable with liquid helium, opens prospects for quantum electronics applications. Unlike aluminum currently used for qubits, magnesium could operate at higher temperatures, reducing costs and environmental impact.
The implications of this discovery could be significant, particularly in quantum computing. Replacing aluminum with magnesium in qubits could make quantum technologies more accessible and sustainable.
Researchers now await experimental confirmation of their predictions. If verified, this breakthrough could mark a turning point in superconductor development and applications.
This study illustrates how theoretical advances can pave the way for major technological innovations. Magnesium, a common element, could thus become a key player in future quantum technologies.
What is quantum confinement?
Quantum confinement describes the increase in a quantum particle's energy when spatially constrained. This phenomenon, related to Heisenberg's uncertainty principle, means the more localized a particle is, the greater its energy fluctuations.
For materials, quantum confinement can radically alter their electronic properties. For example, ultra-thin metal films can see their electrical conductivity transformed, transitioning from a normal state to a superconducting state.
This property opens perspectives for designing new materials with unprecedented functionalities. Researchers exploit this phenomenon to explore previously inaccessible states of matter.
Quantum confinement thus represents a powerful tool for materials science, pushing the boundaries of known physical properties.
Why is critical temperature important in superconductivity?
Critical temperature is the temperature below which a material becomes superconducting. It determines the conditions needed to observe this phenomenon, including the type of cooling required.
A higher critical temperature facilitates superconductivity use by enabling less expensive and more accessible cooling methods. For example, liquid helium, cheaper than other technologies, can be used up to 4.5 Kelvin.
For magnesium, a critical temperature of 10 Kelvin means liquid helium would suffice to reach the superconducting state. This contrasts with aluminum, which requires lower temperatures and thus more sophisticated cooling technologies.
The search for materials with higher critical temperatures is therefore a major challenge to make superconducting technologies more viable and less costly.