The researchers have created 2D sheets, called domain walls, which exist within crystalline materials. Whilst almost as thin as graphene, the sheets are said to appear, disappear or move around within a crystal without permanently altering the crystal itself.
This is said to means that electronic devices could be made even smaller as circuits could reconfigure themselves constantly to perform a number of tasks, rather than just having a sole function.
Professor Marty Gregg, from QUB’s School of Mathematics and Physics, said: “Almost all aspects of modern life – such as communication, healthcare, finance and entertainment – rely on microelectronic devices. The demand for more powerful, smaller technology keeps growing, meaning that the tiniest devices are now composed of just a few atoms.
“As things stand, it will become impossible to make these devices any smaller – we will simply run out of space. One solution is to make electronic circuits more ‘flexible’ so they can exist at one moment for one purpose, but can be completely reconfigured the next moment for another.”
Prof Gregg believes that it may be possible to construct an ‘etch-a-sketch’ approach to creating electrical connections, where patterns of conducting wires can be drawn and erased as often as required.
“In this way, complete electronic circuits could be created and then reconfigured dynamically when needed to carry out a different role, overturning the paradigm that electronic circuits need be fixed components of hardware, typically designed with a dedicated purpose in mind.”
However, two key issues need to be addressed. Long straight walls need to be created in order to conduct electricity and mimic the behaviour of wires. It is also essential that designers can choose where and when the domain walls appear and to reposition or delete them.
The QUB researchers have discovered some solutions and believe that long conducting sheets can be created by squeezing the crystal at precisely the location they are required. The sheets can then be moved within the crystal using applied electric fields.
Dr Raymond McQuaid added: “Our team has demonstrated for the first time that copper-chlorine boracite crystals can have straight conducting walls that are hundreds of microns long and yet only nanometres thick. The key is that, when a needle is pressed into the crystal surface, a jigsaw puzzle-like pattern of structural variants –‘domains’ – develops around the contact point. The different pieces of the pattern fit together in a unique way, with the result that the conducting walls are found along certain boundaries where they meet.
“We have also shown that these walls can then be moved using applied electric fields, therefore suggesting compatibility with more conventional voltage operated devices. Taken together, these two results are a promising sign for the potential use of conducting walls in reconfigurable nanoelectronics.”
