The big squeeze

Big squeeze A crystal of the high-pressure ‘red’ phase of oxygen at 176,000 atmospheres

Dr Eugene Gregoryanz, Dr John Loveday, Dr Malcolm McMahon, Professor Richard Nelmes FRS and Dr Colin Pulham, University of Edinburgh

The world of science at one million times atmospheric pressure

Researchers from the University of Edinburgh are exploring extreme pressures and how they affect ordinary objects to create fascinating new materials.
By squeezing tiny samples of materials between the tips of gem-quality diamond anvils, the researchers can generate pressures up to a million times higher than our Earth’s atmospheric pressure. Using such high pressures can create exotic behaviour not found on the Earth’s surface, providing insight into materials and creating new ones.

“Ninety per cent of the mass in our Solar System is at pressures of more than 100,000 times that of the Earth’s atmosphere, making our ‘normal’ states of matter unusual,” explains Dr Malcolm McMahon from the Centre for Science at Extreme Conditions, University of Edinburgh. “Studies at extreme pressures can therefore help us better understand the state of matter in other parts of our Solar System.”

“Our ‘holy grail’ is to get to the pressure where hydrogen becomes a highly conducting metal, as it is believed to be deep within Jupiter,” continues Malcolm.

Extreme pressures have many applications in our daily lives. It can make semiconductors into superconductors, and destroy bacteria to sterilise food. It can also produce amazing results, such as turning oxygen into dark red crystals or ‘cooking’ an egg without using heat.