Reddit mentions of Magnetic Materials: Fundamentals and Applications

Some people already answered this, but I wanted to add some info on magnets.

Magnets are pretty nifty, let me see if I can help out with some of this. The type of magnet you have on your refrigerator is a ferromagnet. Its polar opposite is nicely named an antiferromagnet. These materials can also take on different forms, if you heat up a ferromagnet higher than its curie temperature, it becomes paramagnetic. If you heat an antiferromagnet up past its neel (nay-el) temperature it becomes diamagnetic.

So what does this mean at an atomistic level?

Electrons have spins that can be polarized in different directions. When you get a group of electrons to all spin in the same direction they create a magnetic field. A magnetic material has a majority of its electrons spinning in the same direction.

With ferromagnets, you can align the electrons by subjecting it to a magnetic field. The electrons will start spinning the same way and form large domains aligned with the induced magnetic field. When you pull the material out of the field, the magnetic effect will persist, because changing spin means breaking a domain wall, which costs energy.

Paramagnets will align when in a magnetic field, but once you take it out they will go back to their chaotic spin states, a paramagnetic material has enough energy to not care about breaking domain walls.

Antiferromagnetic materials have a net magnetization of zero, so for every up spinning electron there's a down spinning electron.

Diamagnets are much like paramagnets, only they don't like magnetic fields entering them. (They have a negative magnetic susceptibility)

Then there are some others, like ferrimagnets, which have electrons spinning in opposing directions, however one of the directions is much more prominent, therefore they act like weak ferromagnets.

If you want a really good book on magnets, check out Nicola Spaldin's book. It's not too physics intensive.


I did want to correct a post someone made earlier though, magnetics are based off of the electronic structure, not the atomic one. You can have single crystal diamagnets, and you can have polycrystalline ferromagnets. The grain structure is not the main contributing factor to magnetism.

There are a lot of good suggestions in here, but I'm wondering if any of them are really applicable to what you want to do. An electrodynamics book like Griffiths will come at magnetism from the perspective of field and/or tensor mathematics. A solid state book like Kittel or Ashcroft and Mermin would come at it starting from a phenomenological perspective and moving into things like local moments and band structure. I'm guessing here, but it seems like what you want is more of an idea of the interaction of magnetism and materials or observable phenomena. Either of those approaches would get you there, but it wouldn't be the most direct approach and it would be a lot more work than you need to put in if that's all you want. They would also both require a lot more math than it seems like you're really comfortable with, and both topics are complex enough that physics/chemistry/MSE students struggle with them without good instructors (and sometimes even with them).

Instead of starting with any of those, I'd suggest you look at some lower level, phenomenology and observation based works. Nicola Spaldin's Magnetic Materials: Fundamentals and Applications might be a good place to start. It's pretty low level: I think a motivated undergrad could deal with it after taking a year of freshman physics, but I think that's what you want, at least to start with. It gives a good overview of different kinds of magnetism and the different kinds of magnetic materials, as well as field generation and detection.

Incidentally, if you decide to be a masochist and go with a solid state book, I think Ashcroft & Mermin is a better text than Kittel. Kittel spent 50 years and eight editions trying to fit the new developments in the field into the book without making it significantly thicker, so Ashcroft has a narrower scope but covers what it does have in more depth. I find the writing style clearer and more accessible as well.