LK-99: Only diamonds are for ever !

No we are not speaking about a new space rocket or a new kind of Covid-19. Topic is supraconductivity !

In July of 2023, a remarkable announcement was made by a team of South Korean scientists. They unveiled a groundbreaking discovery: a new superconductor named LK-99, which operates at room temperature and under ambient pressure conditions. This compound, composed of copper, lead, phosphorus, and oxygen, could potentially mark the first instance of a room-temperature superconductor found in over three decades, holding immense promise for diverse applications.

Interestingly, the moniker "LK-99" derives from the initials of the surnames of the two scientists behind the breakthrough, Sukbae Lee and Ji-Hoon Kim, along with the year 1999 when they initially synthesized this material. The formal presentation of their findings was featured in a publication in the renowned journal Nature on July 12, 2023.

Superconductors are materials characterized by zero electrical resistance, ensuring no energy loss in the form of heat during the transmission of electricity. This unique trait makes them highly suitable for various uses, including power transmission, MRI devices, and magnetic levitation (maglev) trains. Unlike traditional superconductors, which necessitate extremely low temperatures, LK-99 operates at room temperature and ambient pressure. This remarkable property suggests it could enjoy far broader applications than its conventional counterparts.

At present, the highest temperature at which a material has displayed superconductivity is 288 K (15 °C or 59 °F), achieved using carbonaceous sulfur hydride under immense pressures exceeding 267 GPa (over 2.6 million times atmospheric pressure). Regrettably, this material lacks stability under typical conditions, precluding it from being a true room-temperature superconductor.

Commonly used superconductors are metal alloys requiring cryogenic cooling for superconductivity. These materials exhibit critical temperatures ranging from around 10 K (-263 °C or -441 °F) to 100 K (-173 °C or -280 °F). There also exist high-temperature superconductors, functional above the temperature of liquid nitrogen (77 K or -196 °C or -321 °F), with critical temperatures spanning 77 K to approximately 150 K (-123 °C or -190 °F).

In the energy sector, only a few superconducting power lines are in operation worldwide. Among them, the Southwire Demonstration Project in the United States stands out as the longest, spanning 1.3 kilometers and utilizing superconducting cables to transmit electricity at 115 kilovolts. Though its cost of around $100 million surpasses traditional solutions, superconducting power lines offer substantial advantages such as reduced energy loss and heightened resilience to adverse weather.

LK-99's discovery represents a momentous advancement in the realm of materials science, holding the potential to redefine electricity generation, transmission, and utilization. However, certain hurdles must be surmounted before LK-99's widespread implementation can be realized. Among these challenges is its limited stability, as the material deteriorates over time, leading to a loss of superconducting properties within weeks—an obstacle that poses a critical concern, especially for power lines. Additionally, LK-99 exhibits brittleness, making it susceptible to breakage.

Notwithstanding these obstacles, LK-99 offers an extensive array of potential applications. It could revolutionize power line efficiency, render MRI machines more accessible and cost-effective, enhance the speed and energy efficiency of maglev trains, and even facilitate the development of novel electronic devices, including quantum computers.

The path ahead for LK-99 remains uncertain, yet if these challenges are surmounted, its impact could reshape our lifestyles and work environments in unprecedented ways. After all, who's to say that only diamonds are forever?