Reviewed by Lexie CornerMar 13 2025
Researchers on the Cavendish Laboratory, in collaboration with the European Excessive Magnetic Subject Lab in Nijmegen, the College of Warwick, College Faculty London, and Freie Universität Berlin, examined the potential of phosphorene nanoribbons for magnetic and semiconducting properties.
A schematic of the photoexcited dipole dynamics in phosphorene nanoribbons, the place following photoexcitation the excited state relaxes to the ribbon edge. Right here, the excitation is coupled to a symmetry forbidden edge phonon mode and is the place the magnetism is probably going current. Picture Credit score: Arjun Ashoka, Junior Analysis Fellow at Trinity Faculty, College of Cambridge, and Raj Pandya, who was a Junior Analysis Fellow on the Cavendish Laboratory on the time of this analysis and is now on the College of Warwick.
Phosphorene nanoribbons (PNRs), that are just a few nanometers broad, are strips of black phosphorus which have lengthy been thought to own distinctive magnetic and semiconducting properties. Nonetheless, confirming these properties has been difficult.
The researchers explored the magnetic and semiconducting potential of those nanoribbons.
Utilizing methods reminiscent of electron paramagnetic resonance and ultrafast magneto-optical spectroscopy, they demonstrated the magnetic conduct of PNRs at room temperature and the way these magnetic properties work together with gentle.
At ambient temperature, the nanoribbons displayed macroscopic magnetic traits. Iron filings align in resolution beneath comparatively small magnetic fields (<1T), much like their conduct round conventional magnets.
Moreover, these macroscopic magnetic properties had been noticed solely when the nanoribbons had been in skinny sheet kind, similar to the conduct of metals like iron and nickel.
Most excitingly, we found that along with these magnetic properties, PNRs host excited states on the magnetic fringe of the nanoribbon, the place it interacts with atomic vibrations (phonons) which can be usually not allowed by the fabric’s bulk symmetries. This uncommon interplay permits PNRs to uniquely couple magnetic, optical, and vibrational properties on its one-dimensional edge.
Arjun Ashoka, Junior Analysis Fellow and Examine First Creator, Trinity Faculty
“For years, we have explored and utilized the devilish but benevolent 2D surfaces of 3D supplies, from catalysis to machine physics. With these new nanoribbons, we have hopefully unlocked entry to new physics on the 1-dimensional analog of a 2D floor: an edge,” continued Ashoka.
This work is especially noteworthy because it offers the primary experimental affirmation of the anticipated, but challenging-to-observe, magnetic traits of phosphorene nanoribbons.
The affirmation that phosphorene nanoribbons are intrinsically each semiconducting and magnetic—with out requiring low temperatures or doping—is especially essential and novel. Whereas this property was predicted, immediately observing it’s an unimaginable validation of these predictions.
Chris Howard, College Faculty London
Howard’s crew was the primary to synthesize these nanoribbons.
Essentially the most vital side of this analysis is its potential affect on numerous scientific and technological fields. The research might result in the event of spintronic gadgets, which use electron spin as a substitute of cost, enabling developments in computing applied sciences reminiscent of next-generation transistors, versatile electronics, and scalable fabrication for quantum gadgets.
The perfect factor about this work, other than being a very thrilling discovering, has been the nice crew we’ve got labored with over 10 institutes and 5 years, highlighting the superb science that may be achieved after we work collectively.
Raj Pandya, Corresponding Creator, College of Warwick
Raj Pandya was a Junior Analysis Fellow on the Cavendish Laboratory throughout this analysis.
The researchers are centered on the way forward for their work. Their subsequent steps contain investigating how magnetism interacts with gentle and vibrations on the edges of those ribbons and exploring their potential to create new sorts of gadgets.
Journal Reference:
Ashoka, A., et al. (2025) Magnetically and optically energetic edges in phosphorene nanoribbons. Nature. doi.org/10.1038/s41586-024-08563-x
