Majority and Minority Spins VS Up and Down Spins

We hear always about majority and minority spins and about up and down spins. Are they the same or are they different?


We will talk here about when they are the same and when they are different.


Case 01: In non magnetic materials
*********
In this case we talk about up and down spins only which they are equal and there is no majority spins neither minority spins.

Case 02: In ferromagnetic materials
********

In this case we talk about all of them and here they have the same meaning and conventionally they called them as follows:

Majority spin = Up spin
Minority spin = Down spin

Case 03: In antiferromagnetic materials
********

 In this case we also talk about all of them but this time they have different meanings. Here the Up and Down are related to the magnetic atom and we can distinguish between them as follows:

- There are 2 atoms : atom1(Up) and atom2(Down)
- For both atoms there are majority and minority spins
- For atom1(Up), the Up spins are majority spins and Down spins are minority spins
- For atom2(Down), the Down spins are majority spins and Up spins are minority spins.