«It is clear that Cavity Polaritons are a system of choice to explore Boson interactions under quantum conditions.»

—Weisbuch in 2005.

Microcavities in École Polytechnique Fédérale de Lausanne, École Polytechnique (France) and elsewhere: past, present and future. C. Weisbuch and H. Benisty in Phys. Stat. Sol. B 242:2345 (2005).  What the paper says!?

This is an account of the «past, present and future of microcavities» for a symposium held in honour of Marc Ilegems, where it is consigned that the «name cavity polaritons was given at the Erice summer school during some heated sessions (involving in particular the two Elis, Eli Burstein and Eli Yablonovitch) on the nature of these excitations». This makes the volume itself of prime interest for historical purposes.

The paper appears to be essentially taken from another one, written at the same time by the same Authors, to which Weisbuch added personal recollections (switching abruptly and in the most bizarre way to first-person narrative).

There is a great introduction on excitons and polaritons (including in bulk). The most interesting is, however, Section 3 «Looking backwards: a short history of microcavities in solids». There, Weisbuch (in the two-author paper), takes the pen and write: «Let me describe the sequence of events that led to the discovery of CPs» (CP stands for Cavity Polaritons).

The rest describes the rapid growth of polariton research at EPFL (and early EU research projects, SMILES and SMILED, on polaritons).

There is an interesting discussion of light-vs-matter quantum features:

It might prove useful to wonder why it appears that ones gets more leverage when quantizing photons as compared to electron states, or at least why it seems a more useable approach to new phenomena and applications (I know that I will raise some controversy here).

Nice conclusion:

It should be stressed, however, that, as usual for novel fields, the more interesting results and applications will come from concepts that we do not foresee today!