- Researchers demonstrate room temperature laser control of magnons in thin magnetic materials
- Visible light pulses tune magnetic frequencies without cryogenic conditions
- Nanometer scale magnets show promise for faster storage and non silicon computing
Researchers have demonstrated a new way to tune magnetic behavior in extremely thin materials using visible laser pulses at room temperature.
The work focuses on controlling magnons, which are collective spin excitations that play a key role in magnetic devices.
The study, published in Nature Communications, shows that nanometer thick magnets can have their magnon frequencies adjusted both up and down on demand. The material used is just 20nm thick, making it compatible with dense electronic designs.
Myriad possibilities
Magnons are already central to technologies such as hard disk drives and emerging spin based computing concepts. Being able to control their frequency precisely has long been seen as a requirement for practical devices.
In earlier experiments, similar effects were only achieved using mid infrared lasers, cryogenic temperatures, or bulky materials. Those constraints limited any realistic path toward commercial use.
In this new work, the researchers instead used short visible light laser pulses combined with a modest external magnetic field below 200mT. This allowed magnon frequencies to be shifted by as much as 40 percent from their original value.
The experiments were carried out at room temperature using a bismuth substituted yttrium iron garnet film grown on a gadolinium scandium gallium garnet (GSGG) substrate. The film’s low damping and strong magneto optical response proved essential.
By adjusting laser intensity and magnetic field strength, the team could reliably choose whether the magnon frequency increased or decreased.
This level of control comes from the interaction between optical heating, magnetic anisotropy, and the applied field.
The laser pulses act as an ultrafast tuning mechanism rather than a simple heat source. They temporarily change the magnetic stiffness of the material, which directly alters how fast magnons oscillate.
Because the effect operates on nanosecond timescales, it opens the door to magnetic logic elements that can be reconfigured almost instantly.
Such devices could avoid some of the heat and scaling limits faced by silicon electronics.
The combination of room temperature operation, visible light control, and nanometer scale thickness means this approach could fit into future storage, signal processing, and spin based computing systems.
In simple terms, the research could help make everyday technology faster and more efficient, with one of the most obvious uses being in data storage.
Hard drives and large cloud servers rely on magnetic materials, and being able to control them more precisely with light could allow data to be written and moved much quicker than it is today.
It could also to the creation of new kinds of computer chips that use magnetism instead of electrical current to process information.
These would produce less heat and use less power, which could lead to quieter laptops, longer battery life, and – the holy grail for hyperscalers – data centers that are cheaper to run.
Another possible use is hardware that can change what it does on the fly. Instead of a chip being built for a single task, light could be used to switch its behavior almost instantly, allowing one piece of hardware to tackle different jobs.
Because the effect works at room temperature and in layers thinner than a human hair, it isn’t limited to lab experiments either, meaning it could eventually be built into the phones, computers, and portable storage systems that people already use every day.
Follow TechRadar on Google News and add us as a preferred source to get our expert news, reviews, and opinion in your feeds. Make sure to click the Follow button!
And of course you can also follow TechRadar on TikTok for news, reviews, unboxings in video form, and get regular updates from us on WhatsApp too.
https://cdn.mos.cms.futurecdn.net/A7D6Bsqevd9DpG2UW69zcg-970-80.jpg
Source link
waynewilliams@onmail.com (Wayne Williams)
