Ferroelectrics Lecture

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Magnetic Properties of Materials
Auroral Display Tiny particles carrying
electrical charges are always streaming awayfrom
the Sun. Sometimes these get caught in the
Earth's magnetic field and are drawn into the
atmosphere near North and South Poles. When these
charged particles hit molecules in the atmosphere
they cause them to glow with light.
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OUTLINE
5.1. Basic Concepts in Magnetism 5.2. Types of
Magtnetism Diamagnetism, Paramagnetism,
Ferromagnetism, Antiferromagnetism,
Ferrimagnetism 5.3. Langevin Theory of
Magnetism 5.4. Molecular Field Theory 5.5. Applica
tions 5.5.1. Soft Magnetic Materials 5.5.2. Pe
rmanent Magnets 5.5.3. Magnetic Recording and
Memories
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A magnetic field is generated every time an
electrically charged object moves. Most of the
planets in the Solar System are known to generate
magnetic fields. The Earth's magnetic field is
generated in its fluid, outer core. This is
because the heat of the inner core drives the
fluid in the outer core up and around in a
process called convection. Because this outer
core is made of metal, which can be electrically
charged, the convection causes a magnetic field
to be generated.
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Greece
Turkey
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Magnetite opaque, black, ceramic crystal.
Magnetite (FeO Fe2O3) is an oxide of iron
which, unlike Fe2O3, is strongly magnetic.
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The Faraday Experiment
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Electron-Orbit Magnetism
Spin Magnetism
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Diamagnetism and Paramagnetism
Paramagnet, Curie Law, q0
Paramagnet, C-W law with qgt0
Paramagnet, C-W law with qlt0
Diamagnet
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Ferromagnetism
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Formation of Magnetic Domains
Bloch Wall
Bloch Wall and Nèel Wall
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Magnetic Domains
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Magnetization, Susceptibility, Heat Capacity
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Magnetic Anisotropy
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Magnetostriction, Piezomagnetism
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Ferrimagnetism
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Antiferromagnetism
Ordered arrangement of spins of the Mn2 ions in
MnO determined by neutron diffraction. The 02-
ions are not shown.
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Summary
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Thank You.
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