What is room-temperature superconductor? All you need to know about LK-99

Named after two scientists, Lee and Kim, and the year of its discovery — 1999 — LK-99 is a compound made from lead and copper. (Source: Bloomberg)

A group of scientists from South Korea have claimed to have developed a superconductor at room temperature and pressure. The research team published two papers claiming to have discovered the “world’s first room-temperature superconducting material.”

Amid the claimed new discovery, we explain what room temperature semiconductor is and how it is created.

Superconductors are a class of materials that exhibit near-zero electrical resistance. A quantum phenomenon causes electrons to pair up. It allows them to move through the structure of the material with remarkable ease.

This happens only at very low temperatures, near absolute zero or minus 273.15 degrees Celsius, and extremely high pressure. But to achieve these conditions, you require expensive and complex cooling systems such as liquid helium; and this limitation has restricted their widespread practical applications.

A room-temperature, ambient-pressure superconductor can conduct electricity without resistance and without either having to be cooled to almost absolute zero or requiring immense pressure.

Room temperature superconductors could boost the viability of anything that uses electromagnetism and could accelerate the development of a commercially viable fusion reactor. According to Science Journal, it has been referred to as “one of the most sought-after goals in all of materials science and condensed matter physics.”

Two papers published at the Quantum Energy Research Centre and the Korea Institute of Science and Technology, Seoul, claimed to have synthesised a room-temperature superconducting material “for the first time in the world.”

The compound, which they’ve called LK-99, is formed of lead, phosphorous and oxygen.

The researchers claim to have proven LK-99’s superconductivity by demonstrating how the material responds when electricity is pushed through it, or when it is exposed to magnetic fields, all without cooling the material or putting it under pressure.

According to the new research, the material exhibits some of the common characteristics of superconductors, such as zero resistivity, critical current, and a critical magnetic field.

The papers were shared pre-publication which means expert peers have not yet reviewed the work.

According to a Reuters report, researchers from three Chinese universities have in recent days said they produced versions of LK-99 with varying results. A team from the Huazhong University of Science and Technology posted a video showing the material levitating over a magnet, which is important because true superconductors can float over a magnet in any orientation, without spinning like a compass.

But another team, from Qufu Normal University, said they did not observe zero resistance, one of the required characteristics of a superconductor. A third team from the Southeast University in the eastern Chinese city of Nanjing, said they measured zero resistance, but only at a temperature of 110 Kelvin (-163 degree Celsius).

South Korean experts said they would set up a committee to verify the claims.