Exceptional points in classical spin dynamics

November 29, 2019

In a study published in Scientific Reports, researchers offer a theoretical platform for the topology of non-reciprocal spin devices for spintronics and magnonics.

Numerical simulations of encircling an exceptional point (EP) in opposite directions. Regardless of the initial state of the system at the start of the encircling protocols, the loop orientation in the magnetic field plane determines the final state, illustrating non-reciprocal dynamics.

Scientific Achievement

Non-reciprocal topologically-protected time evolution in driven dissipative spin systems is discovered.

Significance and Impact

Our findings enable a high-efficiency spin-filter device based on parametric driving around non-Hermitian spectral degeneracies.

Research Details

Developed a theory of the non-Hermitian spin dynamics in spin-torque-driven dissipative spin systems.
Predicted non-reciprocal time evolution by encircling an exceptional point in configuration space.
Determined optimal protocol parameters for a high-efficiency asymmetric spin-filter effect.

DOI: doi.org/10.1038/s41598-019-53455-0

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