MAGNETISM ELECTRON TRANSPORT MAGNETORESISTIVE LANTHANUM CALCIUM MANGANITE

MAGNETISM AND ELECTRON TRANSPORT IN
1. Introduction
MAGNETORESISTIVE LA 0.67CA 0.33MNO 3
The development of new materials for technological applications has
opened many doors to innovation in the 20 th century. New electronic and
magnetic materials in particular have helped bring about the information
revolution. Much of the progress is due to materials processing.
Technological applications often have strict compositional and
microstructural requirements for their materials. An integrated circuit for
instance must have several compatible semiconductor, dielectric, and
metallic materials with specific properties in precise locations.
Improvements using well understood materials such as these are usually
incremental.
A risky but potentially more revolutionary method for advancing
technologies is to find a different materials which have inherent properties
superior to those currently in use. There are many known materials which
need to be better understood before it would be clear that their use would be a
significant advancement. In some cases a previously unknown class of
compounds (such as the cuprate superconductors) may have to be discovered.
It is also important to consider other aspects of the material, such as chemical
and thermal stability, toxicity and availability.
The study of new materials physics can have different emphasis. Many
physicists are interested in new materials because they can be used to study a
new physical phenomenon. An example of this is the study of heavy
fermion metals and superconductors which have little potential application
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