Although the concept of solitons has been around since Scott Russell's various reports on solitary waves between 1838 and 1844, it was not until 1964 that the word ‘soliton’ was first coined by Zabusky and Kruskal to describe the particle-like behaviour of the solitary wave solutions of the numerically treated Korteweg–deVries equation. At present, more than one hundred different non-linear partial differential equations exhibit soliton-like solutions.

However, the subject of this book is the optical soliton, which belongs to the class of envelope solitons and can be described by the non-linear Schrödinger (NLS) equation. In particular, only temporal optical solitons in fibres are considered, omitting the closely related work on spatial optical solitons.

Hasegawa and Tappert in 1973 were the first to show theoretically that, in an optical fibre, solitary waves were readily generated and that the NLS equation description of the combined effects of dispersion and the non-linearity self-phase modulation, gave rise to envelope solitons. It was seven years later, in 1980 before Mollenauer and co-workers first described the experimental realisation of the optical soliton, the delay primarily being due to the time required for technology to permit the development of low loss single-mode fibres.

Over the past ten years, there has been rapid developments in theoretical and experimental research on optical soliton properties, which hopefully is reflected by the contents of this book.