Effect of Graphene Thin Layer on a Static and Dynamic Magnetostrictive Behavior in TbDyFe Multi-Layered Film for Micro Energy Devices.

Magnetos-mechanical behaviors of TbDyFe/Graphene/TbDyFe film were compared with a tri-layered TbDyFe film to verify the effects of a graphene thin layer on the improvement of magnetic-mechanical performance, as well as decrease of dynamic response time under the low magnetic field. Both of the Heisenberg model and Landau-Lifshitz-Gilbert equation were used to calculate the magnetic domain motion. Time consumptions were simulated to determine a uniformly magnetized state in Graphene and TbDyFe layers. To ensure the magnetostrictive characteristics, the magnetic moment and the magnetostriction were measured using a fabricated magnetostrictive actuator. Compare to the three-layer TbDyFe films, TbDyFe/Graphene/TbDyFe showed a higher magnetostrictive behavior in response to low coercive forces in the range of 0 to 10 kA/m, even with the addition of low magnetic fields. The dynamic magnetostriction response time was faster than the tri-layered TbDyFe film by approximately 24 millisecond.