Summary: metal. This is caused by strong interactions
between the meta-atoms.
Choi et al.1
estimate that a much higher
refractive index -- of a few hundred -- could
be obtained by further shrinking the gaps and
embeddingthelayersofmetamaterialinasub-
strate that has a higher refractive index than
polyimide,forexamplestrontiumtitanate.Such
anindexwouldbearemarkableamplificationof
therefractiveindicesofnature'smaterials.How-
ever, this requires a precision of 10­50 nano-
metres for the manufacture of the metallic
CLIMATE CHANGE
Human influence
on rainfall
Rising concentrations of anthropogenic greenhouse gases in the atmosphere
may already be influencing the intensity of rainfall and increasing the risk of
substantial damage from the associated flooding. See Letters p.378 & p.382
RICHARd P. ALLAN

Source: Allan, Richard P. - Department of Meteorology, University of Reading

Collections: Geosciences