Superconductivity is a state in which a material can conduct electricity without resistance. Normally, when electricity flows through a wire, some of it is lost as heat due to resistance. This is why your phone gets warm when you use it for a long time. However, in a superconducting material, this resistance drops to zero. This means electricity can flow through the material indefinitely without losing any energy.

Most materials need to be cooled to extremely low temperatures, often close to absolute zero (-273.15 degrees Celsius or -459.67 degrees Fahrenheit), to become superconductors. At this temperature something amazing happens: The electrons in the material form pairs and move together in a coordinated way. This pairing allows them to avoid the usual collisions that cause resistance, creating a super-smooth flow of electric current.

The phenomenon of superconductivity was first discovered in 1911 by a Dutch physicist named Heike Kamerlingh Onnes. While experimenting with mercury at low temperatures, he found that its electrical resistance suddenly disappeared. This discovery was groundbreaking and earned Onnes a Nobel Prize in Physics in 1913.

Since then scientists have found many other materials that can become superconductors, including certain ceramics and metals. The race has been on to find superconductors that work at higher temperatures, making them easier to use in practical applications.

Superconductivity is not just a cool trick; it has the potential to revolutionize technology. For instance, MRI machines in hospitals use superconducting magnets to create detailed images of our bodies. Without superconductivity these machines would require much more power and generate a lot more heat.

Another exciting application is in transportation. Maglev trains, like those in Japan, use superconducting magnets to levitate above the tracks, reducing friction and allowing them to travel at incredible speeds. This technology could one day lead to even faster and more efficient trains.

Superconductivity also holds promise for improving our electrical grid. Currently, a significant amount of energy is lost as electricity travels through power lines. Superconducting wires could eliminate this loss, making our energy systems much more efficient and sustainable.

Despite its incredible potential, superconductivity is still a challenging field. The need for extremely low temperatures is a major hurdle, as cooling materials to such temperatures is expensive and difficult. However, scientists are continuously searching for new materials that can become superconductors at higher, more manageable temperatures.

In 1986, researchers discovered a class of materials called high-temperature superconductors, which can operate at temperatures above the boiling point of liquid nitrogen (-196 C, -321 F). This discovery was a breakthrough, but there is still a long way to go.

For decades this quest seemed unattainable. That all changed in 2020, when a team at the University of Rochester created a superconducting material at 59 F (15 C) under extremely high pressures of 3.6 million atmospheres! While impractical for applications, it proved that room-temperature superconductivity is possible.

In 2023, scientists at Harvard and Oxford developed a superconductor operating at 57 F (14 C) under a more manageable 2 million atmospheres. In a more recent breakthrough, researchers at MIT reported an aluminum-based material that becomes superconducting at a remarkable 64 F (18 C) at normal atmospheric pressure.

The ultimate goal is to find a room-temperature superconductor — something that could change the world. If scientists achieve this, it could lead to a new era of technological advancements, from more efficient energy systems to faster computers and beyond.

Superconductivity might seem like a complex and distant topic, but it’s one of the most exciting areas of research today. As scientists continue to unlock its secrets, we could one day live in a world where the flow of electricity is as smooth as silk.

Richard Brill is a retired professor of science at Honolulu Community College. His column runs on the first and third Fridays of the month. Email questions and comments to brill@hawaii.edu.