The characterization and precisely controlled building of atomic-scale mutilayers have been the subject of intensive R&D worldwide. Nanometric structures based on III-V semiconductors have attracted particular attention. Since 1970, around 15,000 papers have been published in all, of which 10,000 have appeared in the last 6 years. The resulting improved materials control is enabling engineers to achieve major improvements in the performance of microelectronic and optoelectronic devices such as QW lasers, tunnelling devices, modulators, switches and photodetectors. In this book, the large volume of research results which have accumulated is evaluated and distilled down to a useful, manageable concentration of up-to-date knowledge for electronic engineers and solid-state physicists. This has been carried out by an invited international team of over 50 specialists under the editorship of Professor Bhattacharya with support from INSPEC, who also compiled the subject index. There are 40 individually-written, self-contained modules ('Datareviews'), each specially commissioned to fit into a pre-determined structure. Subjects reviewed in depth include historical perspective, theory, epitaxial growth and doping, structure (e.g. X-ray diffraction), electronic properties, optical properties, modulation doping and devices. Each Datareview comprises tables, text, figures and expert guidance to the literature, as appropriate. Properties of III-V quantum wells and superlattices is intended both as a look-up source of evaluated data and as a finely-structured state-of-the-art review for academic and industrial R&D workers.

Arsenic contamination has become a global phenomenon. With the development of advanced technological detection tools, more geographical areas have been identified. The people most affected are those in the poorer socio-economic groups. The research articles in this book have been contributed by scientists working in areas severely affected by these difficulties. The book includes an assessment of environmental health risks and economic impacts, and the technologies available for dealing with the problem. Written in a straightforward style, the book is designed to update knowledge on the dynamics of natural arsenic from the aquifers through groundwater to the food chain. It outlines efficient techniques for arsenic removal and inform administrators, policy makers and company executives, and aims to increase awareness of the problem.