Catalan Institute of Nanoscience and Nanotechnology (ICN2) obtained conductivity values for stroncium iridate that were 250 times higher than in normal conditions.

Using an atomic force microscope (AFM) to a press it with nanoscopically sharpened needles at room temperature, researchers showed that the material could become a good candidate for future applications in sensors and electronics. The results were published in Nanoscale.

Piezoresistivity happens when certain materials change their electric conductivity when a deforming pressure is applied. Isolator and semiconductor materials have special electrical characteristics which result in bands with different proprieties: the valence band, where electrons are "parked," and the conduction band, where the electric current flows. These bands are separated by an energy gap. When the gap is thin, the number of electrons in the conduction band is higher and, consequently, the electric conductivity also is higher. This opens a range of possible applications, from pressure sensors to microelectronic transistors where the current is controlled by pressure instead of voltage.

The semiconductor could be a good candidate for future applications in sensors, new kinds of transistors and other specialized electronic devices. However, iridium is a scarce element, so scientists are looking for alternative materials.

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