A group of South Korean scientists has discovered the existence of dark states of electrons in a solid material for the first time in the world in a joint research project with scientists from the United States, Britain and Canada, the science ministry said Monday.A research team, led by Professor Kim Keun-su at Yonsei University in Seoul, posted a paper titled "Dark States of Electrons in a Quantum System with Two Pairs of Sublattices" on Nature Physics, a prominent science journal, according to the Ministry of Science and ICT.A dark state refers to the state of an atom or molecule that cannot absorb or emit photons, and a dark state of electrons had been widely believed to be not able to exist in solids.Kim's team found that electrons undetectable in copper oxide of a high-temperature superconductor were dark states while studying a quantum system with two pairs of sublattices."There are dark states of electrons in many materials around us," Kim said. "Our next target is to solve problems related t o high-temperature superconductivity, a long standing conundrum in modern day physics, based on our findings."High-temperature superconductors, materials with critical temperature, are considered to have the potential for creating innovations in the energy, transportation and medical industries as they can be easily cooled with liquid nitrogen.Source: Yonhap News Agency