exchange bias

[mhill]

Could someone explain me an elementary introduction to this phenomenon ?

i know that it is produced whenever an ANTIFERROMAGNETIC and a FERROGMAGNETIC materials are put together , however my doubts are

- is this 'exchange bias' produced by any spin interaction ??

- i can see the figures however i do not know how to interpretate the following .png

http://en.wikipedia.org/wiki/Image:Exchangebias.png

it seems that the Hysteresis cycle is 'modified' but how is this used ??

If someone can give me an introduction to exchange bias thank you

[badphysicist]

Well, no one else has posted so here's what I gather about this. Yes, it is a spin interaction because it is caused by the exchange interaction which causes particles to either be closer or further apart depending on their spins and one form of exchange interaction is modeled in the Heisenberg model.

What you are supposed to notice from the image is that the hysteresis is shifted to the left by a certain amount. That shifting is the exchange bias. It biases the magnetic field. One important usage is to make permanent magnets which should make sense from looking at the diagram. Here's a paper that you might want to read the beginning of:
http://www2.hmc.edu/~eckert/research/schull.pdf