Transcript seminario di fisica - Scuola Normale Superiore

SEMINARIO DI FISICA
Mercoledì 1 febbraio 2017
ore 11:00
Scuola Normale Superiore
Pisa
Aula Marie Curie
Simon Horsley
(Department of Physics and Astronomy - University of Exeter, UK)
terrà un seminario dal titolo:
“Wave propagation in the complex plane:
reflectionless and invisible metamaterials”
Abstract:
It is easy to solve the wave equation in free space - any function f(x+/-ct) will do. It is much less
straightforward to find the solution inside a material when the wave speed changes as a function of
position. Yet this is often the situation we face: from ocean waves traveling over a sea-bottom of
changing depth, to quantum waves of atoms passing through interfering laser fields. The field of
metamaterial research is concerned with controlling bulk material properties such as wave speed,
through building the material from small man-made elements - `meta-atoms'. Starting from this point of
view, in this talk I shall address the question: if we can control the wave speed as a function of position,
then what would I need to do to suppress reflection, or even make a material invisible? I shall show that
it is helpful to explore the analytic continuation of the wave equation, and that properties of the wave in
the complex position plane such as poles and branch cuts have a simple physical interpretation. This can
be used to control the reflection and transmission of a wave. As a rather extreme extension I shall then
show that there exist a family of random media where there is no Anderson localization, and where the
transmission is always 100%.
Tutti gli interessati sono invitati a partecipare.
Classe di Scienze Matematiche e Naturali
Piazza dei Cavalieri, 7
56126 Pisa-Italy
tel: +39 050 509111
fax: +39 050 563513
23/01/2017