The performance of devices such as mobile phone cameras and solar cells could be boosted by 'nano earthquakes', according to researchers from Australia's RMIT University.
In a study led by Dr Sharath Sriram, Drs Sumeet Walia, pictured left, and Amgad Rezk have examined the use of sound waves to change the electronic properties of 2D materials. The researchers say their findings have important implications for electronics and optoelectronic devices made from 2D materials and believe their work could herald a new era of highly efficient solar cells and smart windows.
The RMIT research looked at ways of using surface acoustic waves – what the team calls nano earthquakes – to control the properties of 2D materials.
"Sound waves can be likened to ripples created on the surface of water, but where we can control the direction and intensity of these ripples," Dr Walia said. "In this work, we use these ripples which occur on a crystal surface and couple them into a material that is a few atomic layers thick. This causes a change in its electronic properties.
"As the surface acoustic waves are turned on and off or increased and decreased in intensity, the change in electronic properties of the 2D materials follows the same pattern."
Dr Rezk added: "We have found [these waves] under the surface of the 2D materials drag electrons along their path, tuning the amount of light emitted by the material. Remarkably, the acoustic wave based tunability did not result in any structural or compositional change in the material.
"As soon as the acoustic waves were removed, the material retracted back to its initial optical state and therefore this mechanism is highly adaptable for a variety of dynamically operating systems."
