Microscopic origin of the intriguing behaviour of nickelates. Depending on whether or not they conduct electricity, materials are typically classified as either conductors or insulators. But is it that simple? Can the same material eventually change its behaviour depending on the environment in which it is placed? This is the case of some compounds such as nickelates, a series of complex oxides of perovskite structure. Depending on the temperature, these materials can change from electrical conductors to insulators in an abrupt and reversible way, a transformation that is as unusual as it is intriguing.   Alain Mercy and Philippe Ghosez, in collaboration with researchers of CEA and LIST reveal the microscopic mechanism behind this change of state. Learn more here !   See also the advertisement on Daily Science !

Structurally triggered metal-insulator transition in rare-earth nickelates. A. Mercy, J. Bieder, J. Iñiguez and Ph. Ghosez, Nature Communications 8, 1677 (2017).