Trinity researchers from the School of Physics and the Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) have created a new material which has enabled them to perform magnetic switching at ultra-fast speeds. This could have significant effects on data storage and how efficiently our global fibre optic network functions.
In this digital age, information from all over the world is stored in groups of binary states, 0 or 1, and switching between these states forms the basis of modern-day technology and the internet. The data held in these binary states is stored magnetically in data centres spread across the globe, which are connected by a network of fibre optic cables.
Since our technology today is dependent on the ability to switch between states, increasing the speed of this switching could greatly increase the efficiency of data storage.
Currently, scientists face three main challenges when it comes to progressing further with the internet. Firstly, they are struggling to increase the speed of these magnetic switches. Secondly, they need to find a way to lower the energy consumed by switching states. Finally, before any considerable change is made in data storage for the internet, the fibre optic network must also be improved to handle it.
The new ultra-fast switch developed by the Trinity team, including Dr Chandrima Banerjee and Dr Jean Besbas, could help solve all three problems.
The switch is made of thin, mirror-like films made of an alloy of manganese, ruthenium and gallium (MRG). High-speed laser pulses, that last only one ten thousand billionth of a second, strike the MRG film and create a “toggle switching” effect. The magnetistaion of the film can point in and out of the film, and the switch changes this direction. The team has hypothesised that this occurs because the electrons within the alloy are heated approximately 1000 degrees by the laser, giving them the energy to switch states.
This is faster than conventional switches, which helps solve the issue with switch speeds. These MRG switches, because of their magnetic nature, require no power to maintain their state. They also show the potential to increase the capacity of the global optical fibre network tenfold, by increasing the speed of an optical method called time-domain multiplexing.
Dr Karsten Rode, a Senior Research Fellow in the Magnetism and Spin Electronics Group in Trinity’s School of Physics, said that the discovery leads to many interesting questions about the behaviour of the electrons in the MRG film.
“We have a lot of work to do to fully understand the behaviour of the atoms and electrons in a solid that is far from equilibrium on a femtosecond timescale,” Rode said.
“In particular, how can magnetism change so quickly while obeying the fundamental law of physics that says that angular momentum must be conserved?”
The team, led by Rode, intend to test their hypothesis that the toggle switching phenomenon occurs only due to the electrons being heated and will continue laser experiments on the MRG films. They plan to collaborate with other researchers from France, Norway, Switzerland and the Netherlands to reach their goal of ulta-fast time domain multiplexing of fibre optic cables.
