Doubts About LK-99 Superconductor Claim Sink Korean Stocks

South Korean stocks linked to superconductors plunged Tuesday after a US-based research center rebutted claims of a sensational breakthrough in the technology, heaping pressure on scientists to validate those findings as soon as possible.

The University of Maryland’s Condensed Matter Theory Center challenged claims made by the Seoul-based Quantum Energy Research Centre that it synthesized a material capable of conducting electricity with zero-resistance at room temperature and ambient pressure, known as LK-99.

The extraordinary reports have transfixed the world and energized the scientific community in recent weeks, driving rallies particularly in South Korea but also on Chinese bourses as investors ...