Rare Earth and Transition Metal Doping of Semiconductor Material explores traditional semiconductor devices that are based on control of the electron's electric charge. This book looks at the semiconductor materials used for spintronics applications, in particular focusing on wide band-gap semiconductors doped with transition metals and rare earths. These materials are of particular commercial interest because their spin can be controlled at room temperature, a clear opposition to the most previous research on Gallium Arsenide, which allowed for control of spins at supercold temperatures. Part One of the book explains the theory of magnetism in semiconductors, while Part Two covers the growth of semiconductors for spintronics. Finally, Part Three looks at the characterization and properties of semiconductors for spintronics, with Part Four exploring the devices and the future direction of spintronics.

This book deals with the mutual interaction and energy transfer between electronic defect states of F centers and defect ions (e.g. rare earth elements) and neighbouring molecular defects (OH-, CN-) in alkali halides. These model defect systems exhibit a very intriguing and ambiguous character because they behave like isolated defects in one instance but like supermolecules in others. The text gives an overview of the topic and discusses possible applications. It covers a wide range of spectroscopic methods applied to the systems and reviews several approaches for their theoretical interpretation. It includes more than 100 illustrations, figures and tables as well as many previously unpublished results. This book provides a valuable resource for further studies into this and related fields.

It has been noted several times previously that the Rare Earths (RE), a sequence of elements with atomic numbers in the range from 58 (Ce) to 71 (Lu), are neither earths nor particularly rare. They are metals, whose ores are often found together with oxides of the "alkaline earths" (Ca, Mg), staples of the building industry, th while Cerium, for example, is the 25 most abundant element in the Earth's crust. However, the chemical similarity of all REs to each other and to Lanthanum, reflected in their alternative descriptor, Lanthanoids, made extraction of the separate elements difficult until technical advances in the 1960s kick-started the modern era of RE science. The most widespread commercial use of RE metals at present is in the prod- tion of super-strong permanent magnets, containing Neodymium: check your refrigerator door for an example. RE ferromagnetism arises from the angular momentum of electrons in partially filled 4f atomic shells. In chemical compounds of RE with non-metals, the 4f shell is surrounded by filled 5s and 5p orbitals, 1 2 while bonding involves the outerlying 5d and 6s electrons, resulting (usually) in 3+ 3+ a RE ion that is chemically similar to La . (RE may also be found in a divalent charge state, with an 'extra' electron in the 5d shell. ) Hence the sequence of 3+ 3+ trivalent ions from Ce to Yb is characterised by a 4f shell occupation that rises from 1 to 13 electrons.

It has been noted several times previously that the Rare Earths (RE), a sequence of elements with atomic numbers in the range from 58 (Ce) to 71 (Lu), are neither earths nor particularly rare. They are metals, whose ores are often found together with oxides of the "alkaline earths" (Ca, Mg), staples of the building industry, th while Cerium, for example, is the 25 most abundant element in the Earth's crust. However, the chemical similarity of all REs to each other and to Lanthanum, reflected in their alternative descriptor, Lanthanoids, made extraction of the separate elements difficult until technical advances in the 1960s kick-started the modern era of RE science. The most widespread commercial use of RE metals at present is in the prod- tion of super-strong permanent magnets, containing Neodymium: check your refrigerator door for an example. RE ferromagnetism arises from the angular momentum of electrons in partially filled 4f atomic shells. In chemical compounds of RE with non-metals, the 4f shell is surrounded by filled 5s and 5p orbitals, 1 2 while bonding involves the outerlying 5d and 6s electrons, resulting (usually) in 3+ 3+ a RE ion that is chemically similar to La . (RE may also be found in a divalent charge state, with an 'extra' electron in the 5d shell. ) Hence the sequence of 3+ 3+ trivalent ions from Ce to Yb is characterised by a 4f shell occupation that rises from 1 to 13 electrons.

This up-to-date text deals with the mutual interaction and energy transfer between electronic defect states of F centres and defect ions and neighbouring molecular defects in alkali halides. It includes more than 100 illustrations and figures, plus many previously unpublished results.