A magnetic impurity is an impurity in a host metal that has a magnetic moment. The magnetic impurity can then interact with the conduction electrons of the metal, leading to interesting physics such as the Kondo effect, and heavy fermion behaviour. Some examples of magnetic impurities that metals can be doped with are iron and nickel. Such an impurity will contribute a Curie-Weiss term to the magnetic susceptibility, .
Early theoretical work concentrated on explaining the trend observed as the impurity was varied across the transition metal group. Based on the idea of a virtual bound state, Anderson proposed a model that was successful in explaining the formation of a localized magnetic moment from a magnetic impurity.
Famous quotes containing the words magnetic and/or impurity:
“We are in great haste to construct a magnetic telegraph from Maine to Texas; but Maine and Texas, it may be, have nothing important to communicate.”
—Henry David Thoreau (1817–1862)
“Purity is not imposed upon us as though it were a kind of punishment, it is one of those mysterious but obvious conditions of that supernatural knowledge of ourselves in the Divine, which we speak of as faith. Impurity does not destroy this knowledge, it slays our need for it.”
—Georges Bernanos (1888–1948)