continued interest in VPE, albeit for limited epilayer com-positions, for some years to come. The adaptation of VPEto a continuous throughput process is certainly attractive,although the complexity of the growth chamber for such asystem arouses some apprehension.

The final section, which at first sight might appear to beout of place in a work concerned with epitaxy, deals withdefects in III-V semiconductors. The information present-ed is good but limited in scope. It deals mainly with GaAsand (Ga,Al)As, ignoring the currently important(Ga,In)(P,As) materials. However, the most serious criti-cism is that the material dealt with tends to be dated anddoes not adequately reflect the progress made, for example,in high resolution studies of interfaces that are currentlygiving useful information in all types of epitaxy. Perhaps amore valuable final chapter would have dealt with state-of-the-art characterisation techniques for epitaxial structures,and the information that can be derived from them toidentify the defects of importance to device-structure effi-ciencies.

It is easy to be critical of an attempt to cover a special-ised field of science or technology, and particularly amultidisciplinary subject which allows many directions ofinterest to diverse readers to be pursued. The presentvolume is certainly to be welcomed, and will doubtless beavidly devoured by those concerned with epitaxy in itsvaried forms. The question is: how valuable is it as anintroduction for newcomers to the field?

E.A.D. WHITE

4926J

Physics of new laser sourcesN.B. Abraham, FT. Arecchi, A. Mooradiam and A. Sona,(Eds.)Plenum Press, 1985, 492 pp., $75 (20% higher outside USAand Canada)ISBN 0-306-42105-4

This book contains the lectures and seminars presented atthe NATO Advanced Study Institute on 'Physics of NewLaser Sources' held at San Miniato, Tuscany, July 11-211984. The Editors in their Preface, state the intention ofthis ASI as being 'to provide an understanding of theadvantages and potential applications of maturing newsources and to provide the basis for participants to evalu-ate and explore uses of even more novel sources currentlyunder design or development.'

The book contains 27 contributions in all, ranging typi-cally between 10 and 30 pages in length. As with all suchmulti-author collections, there is an inhomogeneity ofquality, as the curate discovered in his egg. There arehowever a sufficient number of good reviews to make thisa worthwhile source of material. Some of the reviews willclearly not improve with age and already some of thematerial has been superseded by the rapid turn of events.Two years is a long time in the field of lasers. So the use-fulness of this book is already somewhat diminished by thepassage of time. Nevertheless, there is enough in it to

justify its inclusion on library shelves. Anyone using thisbook should, however, realise that it does not give a trulycomprehensive picture of the current state of laser devel-opment. For example, it has little to say about the strikingdevelopments that have taken place in solid-state lasersover the last few years, apart from one chapter on theAlexandrite laser. So the usefulness of the book resides notin comprehensiveness but in the good quality of a numberof individual contributions.

In what follows, the titles of a number of review will begiven, so as to give the potential reader some idea of thetopics covered. First however, mention should be given toa few topics which do not (to me) seem to have a place in avolume with this title. Their inclusion is a bit of a mystery.Try for example, 'Two possible measurements of the effec-tive mass of electrons injected into a liquid', or 'Selectedtopics in laser spectroscopy'. The military and industrialinterest in lasers is reflected in a number ofcontributions—this makes more sense. For example, thereare 'An Er3 +: Glass eye-safe military laser', 'Eye-safe lasersfor military applications'.

A listing of some of the more useful contributionsshould include the following:

Tunable short-wavelength laser sources, by StoicheffProperties of Alexandrite lasers, by WallingExcimer lasers: practical excimer laser sources, by

BurlamacchiSpectral characteristics of semiconductor diode lasers,

by MooradianExtension of semiconductor lasers to higher power

and longer wavelength, by LangHigh power, tunable waveguide CO2 lasers, by

Strumi and IoliMid-infrared optically pumped molecular gas lasers,

by Harrison and RuttOptocally pumped far-infrared lasers, by Strumia et al.Free-electron laser experiments, by BrauThe free-electron laser, by RenieriSynchrotron radiation sources and uses in the

UV-VIS, by PiacentiniPhase-conjugation: techniques and applications, by

Giuliano and RockwellWavelength conversion by stimulated Raman scat-

tering, by Rockwell and Bruesselbach.

One further contribution should be mentioned, by Grisch-kowsky, on pulse compression. This contribution takes theform of five selected reprints on the subject of pulse com-pression. The editors in their preface suggest that thisapproach 'may ultimately become the standard route toefficient surveys of this type without the labor of preparingredundant camera-ready manuscripts'. Certainly the con-venience for everyone concerned cannot be denied.However, excellent as those reprints are, this does not havethe same value and appeal to the reader as an article spe-cifically written as an introduction and survey of the field.So, while I welcome this book as useful addition to theliterature, I am not sure that I would say the same for abound collection of reprints.

D.C. HANNA

4927J

358 IEE PROCEEDINGS, Vol. 133, Pt. J, No. 6, DECEMBER 1986