Amazing stuff! Not easy to understand though for non experts!
"Spintronics explores magnetic phenomena in nano-thin layers of magnetic materials that are exposed to magnetic fields, electric currents and voltages. These external stimuli can also create spin waves, ripples in a material's magnetisation that travel with a specific phase and energy.
The researchers can generate and control the spin waves, enabling a phase controlled mutual synchronization between two so-called spin Hall nano-oscillators. By controlling the phase of these waves, the research team was able to generate binary phases across the network. For the first time, they showed that spin waves can mediate both in phase and out of phase between the oscillators. The phenomenon can be tuned by adjusting either the magnetic field, the electric current, the applied gate voltage or the distance between the oscillators.
These advances pave the way for the next generation of Ising machines, an alternative to quantum computers that require much less energy and can operate at room temperature. ...
Ising machine
An Ising machine is a new type of computational system that mimics how magnetic spins in a physical material organise themselves to reach a stable state. It is mainly used to solve complex optimisation problems in an efficient way. Rather than calculating step-by-step as in conventional computers, the system's many small ‘spins’ work together to quickly find the best solution. The Ising machine is programmed by the strength of the connections between the different spins. If the coupling is positive, the spins will point in the same direction (in phase) and if it is negative, they will point in the opposite direction (out of phase). The solution to the problem is then read out as the final direction of all the different spins after they have been optimally aligned."
From the abstract:
"Spin–orbit torque can drive auto-oscillations of propagating spin-wave modes in nano-constriction spin Hall nano-oscillators. These modes facilitate both long-range coupling and the possibility of controlling their phase, which is a crucial aspect for device application. Here, we demonstrate variable-phase coupling between two nano-constriction spin Hall nano-oscillators and their mutual synchronization driven by propagating spin waves.
Using electrical measurements and phase-resolved micro-focused Brillouin light scattering microscopy, we show that the phase of the mutual synchronization can be tuned by modulating the drive current or the applied field. Our micromagnetic simulations explore the phase tunability using voltage gating. Our results advance the capabilities of mutually synchronized spin Hall nano-oscillators and open the possibilities for applications in spin-wave logic-based devices."
Breakthrough in the development of a new low-cost computer (original news release) "A low-energy challenger to the quantum computer that also works at room temperature may be the result of research at the University of Gothenburg. The researchers have shown that information can be transmitted using magnetic wave motion in complex networks."
Spin-wave-mediated mutual synchronization and phase tuning in spin Hall nano-oscillators (open access)
Fig. 1: Device fabrication and electrical observation.
No comments:
Post a Comment