Optimal switching of a nanomagnet assisted by microwaves

Physics – Condensed Matter – Materials Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

9 pages, 8 figures

Scientific paper

We develop an efficient and general method for optimizing the microwave field that achieves magnetization switching with a smaller static field. This method is based on optimal control and renders an exact solution for the 3D microwave field that triggers the switching of a nanomagnet with a given anisotropy and in an oblique static field. Applying this technique to the particular case of uniaxial anisotropy, we show that the optimal microwave field, that achieves switching with minimal absorbed energy, is modulated both in frequency and in magnitude. Its role is to drive the magnetization from the metastable equilibrium position towards the saddle point and then damping induces the relaxation to the stable equilibrium position. For the pumping to be efficient, the microwave field frequency must match at the early stage of the switching process the proper precession frequency of the magnetization, which depends on the magnitude and direction of the static field. We investigate the effect of the static field (in amplitude and direction) and of damping on the characteristics of the microwave field. We have computed the switching curves in the presence of the optimal microwave field. The results are in qualitative agreement with micro-SQUID experiments on isolated nanoclusters. The strong dependence of the microwave field and that of the switching curve on the damping parameter may be useful in probing damping in various nanoclusters.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Optimal switching of a nanomagnet assisted by microwaves does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Optimal switching of a nanomagnet assisted by microwaves, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optimal switching of a nanomagnet assisted by microwaves will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-639341

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.