COST, European Cooperation in the Field of Scientific
and Technical Research, was established in 1971 as a framework
for scientific and technical cooperation, allowing the
coordination of national research on a European level. COST
Actions consist of basic and precompetitive research. The goal
of COST is to ensure that Europe holds a strong position in the
field of scientific and technical research for peaceful
purposes, by increasing European cooperation and interaction in
this field. COST has developed into one of the largest
frameworks for research cooperation in Europe and is a valuable
mechanism coordinating national research activities at European
level. Today its nearly 200 Actions involve some 40000
participating scientists from 32 European member countries and
nearly 50 more participating institutions from an additional 14
countries. These networks represent a value of more
than 
2 billion.
The Technical Committee of Physics is the most recently formed of
the COST Technical Committees, having been approved in 1997, and
currently consists of six Actions. The COST Action P2,
Applications of Nonlinear Optical Phenomena, has been running
since 1997 and has to date been signed by 16 member countries.
In the frame of this Action a general workshop is held every
year: the second general workshop was held in Amalfi (Italy)
from 6-9 October 1999, with the title `Applications of Nonlinear
Optical Phenomena and Related Industrial Perspectives'.
Our aim was to provide an industrial and academic forum for
presentations and panel discussions on the state-of-the-art
nonlinear optical phenomena applications in Europe. Further, we
wanted to allow for open discussions on current industrial
and academic achievements, as well as future perspectives in
this area. For this purpose the Workshop was also open to
scientists not belonging to the COST Action P2 and it was promoted
all over Europe.
The Workshop was held in Amalfi at the Hotel Cappuccini
Convento. This is a prestigious Hotel in a historical monastery
dated from the 11th century, which provided a most enjoyable and
suitable location for a very exciting scientific meeting. By
unanimous consent this event was a complete success in every
aspect, but primarily in the scientific one. During the three
and a half days of the Workshop, we had 77 registered
participants, 4 keynote speakers, 6 invited chairpersons and
speakers, 21 contributed speakers, 18 poster presentations and 2
general discussions, plus the Management Committee meeting of
the Action P2. The whole organization of the Workshop was our
attempt to fulfil the spirit of COST. We hope to have at least
partially reached this objective, and we wish that new fruitful
collaborations will establish themselves and that old ones may become
stronger. The Management Committee of the COST Action P2 can
confirm these results since the next general workshop is in
Twente, Netherlands, in October 2001.
The workshop was not intended to be a small topical conference
but instead, as said before, a forum for discussions;
nevertheless the scientific content of the presentations was on
average very high. Thus, in order to keep a permanent record of
the presentations given and of the most important scientific
achievements discussed in Amalfi, and with the support of the
Management Committee of the COST Action P2, two important
initiatives were taken.
The first was the realization of a CD-ROM containing the
relevant information about the Workshop, namely the programme,
the list of participants, the list of abstracts and all the
available presentations in electronic format.
The second, in agreement with Institute of Physics Publishing
and the Editors of the journal, was the publication of a selected
number of original papers presented in Amalfi in this special
issue of the Journal of Optics A: Pure and Applied
Optics. The papers published were selected and submitted to
the standard peer review procedure of the journal. The
reviewing was performed strictly following the rules and
indications of the journal by a number of experts in the field:
they deserve our gratitude for their time and contribution to
ensuring the high scientific quality. Many aspects of
nonlinear optical applications are covered, ranging from
telecommunications to optical data storage and pattern
recognition, as well as hot topics such as photonic band gaps.
Some very interesting and important papers deal with molecular
engineering, which is a crucial point in the challenge amongst
NLO materials. The issue opens with a review article by
Toskikuni Kaino, which gives a highly valuable overview of
recent developments of polymeric materials for NLO. Showing the
possibility to overcome many of the drawbacks of older polymeric
optical devices, it gives a possible explanation of the
re-growing interest of the NLO community in these kind of
materials.
For the financial support that permitted not only the
organization of the workshop but also the realization of this
special issue, we are indebted to the Department of Physical
Sciences of the University of Naples Federico II, to the
Istituto Nazionale per la Fisica della Materia INFM and to the
COST Secretariat.
As guest editors, we thank all those who submitted their
contribution for inclusion in this special issue. Special thanks are
also due to the editorial staff of the journal, who supported and
helped us in our work.