MH loop of Para, ferro, ferri and anti-ferromagnetic material

1. Assignment:
Solid statePhysics
Submittedto:
Dr.Muhammad Kamran
SubmittedBY:
MehakTariq
RollNo.
PHY-M-18-17
GHAZIUNIVERSITY DERAGHAZIKHAN

2. MHloopofPara,ferro,ferriandanti-ferromagnetic
material
Before starting this topic, let me mention a few things that will help us
understand this topic.
These are as follows:
 Para magnetic material
 Ferro magnetic magnetic
 Anti-ferromagnetic material
 Ferrimagnetic material
 Dia magnetic material
Diamagnetic material is repelled by magnetic moment because of
-ve magnetization and have zero magnetic moment.
Para magnetic material have little magnetic moment and is randomly
aligned.
Ferro magnetic material is magnetized even we remove the magnetic
field and this process is called hysteresis.
Ferrimagnetic material In such material some magnet domains are in
same and some are in opposite direction.

3. Anti-ferromagnetic material magnet domains in such materials are
aligned in opposite to neighboring atoms.
Curie temperature is the temperature above which certain materials lose
their permanent magnetic properties. Pierre Curie showed that magnetism
lost at a critical temperature.
MHloopofPara,ferro,ferriandanti-ferromagnetic
material
We applied magnetization at y-axis and at x-axis applied magnetic field is
applied. As soon as we start magnetization we will gradually
increase the power. There will come a time when magnetization
will become linear. We will increase the power, everyone will try to
get in order as soon as possible, and yes, there is a relation to a
certain extent, which will increase in power, we will try to get in
order, but in case of low power, then return to normal.... This
means that if you keep it in the magnetic field, it will be
magnetized. If you remove the magnetic field, it will return to
normal.
This will be a paramagnetic behavior. If we increase the power and reach
the saturation level, then the field where the power is obtained is
spontaneous,then we will increase the field as much as possible but there
will be no magnetization after reaching the saturation level we again
decrease the power.

4. That will change and it will become a permanent magnet.it is not
so easy to make a ferro magnet material a permanent magnet. If
we want to do this then applied magnetic field should be sufficient
high so much so could reach the saturation level.
Now if we decrease the power then magnetization will also
decrease, but not as much as before… There will still be
magnetization and this is called remnant magnetization. It is the
remnant magnetization that generates permanent magnet. At low
magnetic field there is para magnetic behavior. If we have ferro
magnetic material then at low power it will show linear behavior. If
we reverse the poles of magnet then the induced magnetic field
will be known as coercive field.
The magnetic susceptibility, χ, of a solid dependson
the ordering of spins. Paramagnetic, ferromagnetic,
antiferromagnetic, and ferrimagnetic solids all have χ > 0,
but the magnitudeof their susceptibilityvaries with the kind
of ordering and with temperature. We will see these kinds

5. of magnetic ordering primarily among
the 3d and 4f elements and
their alloysand
compounds.
Below a certain critical
temperature, the spins of a
solid paramagnetic substances
order the susceptibility
deviates from simple curie-law
behavior. critical temperature
varies depends upon the short-
range exchange interaction.
metals and alloys in 3D series tend to high critical temperature. Metal
atoms are bounded strongly to each other. In between force attraction
is strong. For example, Fe and Co have critical temperature called curie-
temperature. Paramagnetic salts of transition metal ions typically have
critical temperature below 1K, because magnetic ions are not directly
bonded to each other.
magnetic susceptibility x depends on ordering of spins. Para ferro, ferri
and antiferromagnetic solids all have susceptibility greater than 0. But
magnitude of their susceptibility varies with the kind of ordering and
with temperature. Kinds of magnetics ordering Primarily among the 3D
and up element.

6. For example, Fe, Co, Ni all are ferromagnetic. Co and MnO are
Antiferromagnets and Fe3O4 and CoFe2O4 are ferrimagnets.
Diamagnetic compounds have a weak -ve susceptibility.