Magnets of all types, from simple souvenirs to put on the refrigerator to disks that gives memory to the computer and powerful ones used in research labs – comprise spinning quasiparticles called magnons. The direction in which magnon spins can influence its neighbor, which further influences spin of its neighbor, for the pattern to continue, resulting in what is known as spin waves.
Transfer of information via spin waves is potentially more efficiently than electricity, and magnons can work as ‘quantum interconnects’ that attach quantum bits together into advanced computers.
Magnons have tremendous potential, but it is often challenging to detect them without bulky lab equipment. “Such setups are suitable for experiment purposes, and not for developing devices,” stated a researcher at Columbia.
In an article published in Nature, a collaborative team of researchers demonstrated that magnons in CrSBr can team up with another quasiparticle called exciton, which discharges light, thereby offering the researchers a way to ‘view’ the spinning quasiparticle.
On perturbing magnons with light, oscillations were observed from the excitons in the near-infrared range, which is nearly in the visible spectrum of the human eye. “For the first time, magnons were visible with a simple optical effect,” added the Columbia researcher.
The results obtained can be viewed as quantum transduction, or conversion of one ‘quanta’ of energy into another, stated the first author of the study. The energy of excitons is four times larger than magnons in magnitude; now, because they team together strongly, any change in the magnons can be easily observed.
This transduction of energy, may one day enable researchers to create quantum information networks that can derive information from spin-centred quantum bits, and transform it into light.