13.1 Introduction

What are optoelectronic devices? I do not think it is easy to answer this question; as far as I know, there is no accepted definition. There was certainly a time when people talked about photoelectronic devices. I believe they were devices which had something to do both with photons and electrons, in particular with the interaction of light with electrons. Then there was (and still is) electro-optics, concerned with the effect of electric fields upon the propagation of light. So, maybe we should define optoelectronics as a broader discipline which covers both photo-electronics and electro-optics. But what about the interaction of light and acoustic waves, or nonlinear optics, are they part of optoelectronics? We seem to be driven towards the definition that any modern way of manipulating light (interpreted generously, so as to include infrared and ultraviolet) will qualify as optoelectronics.

Some cynics have an alternative definition. They maintain that this new subject emerged when the relevant grant-giving authorities (on both sides of the Atlantic) came to the conclusion that they had very little money to spare for research in the traditional subjects of photoelectronics, electro-optics, acousto-optics, etc. So those compelled by necessity to spend a considerable part of their time writing grant applications invented a revolutionary new subject with a brilliant future ...

Having decided that optoelectronics is...