Electromagnetic surfaces from butterflies to battleships

Add to your list(s) Download to your calendar using vCal

• Professor J Roy Sambles, School of Physics, University of Exeter
• Wednesday 13 May 2009, 16:15-17:15
• Pippard Lecture Theatre, Cavendish Laboratory.

If you have a question about this talk, please contact Leona Hope-Coles.

Question: What do graceful, flickering, vividly iridescent, tropical butterflies have in common with dull grey ponderous battleships?

Answer: Structured materials give somewhat surprising electromagnetic responses.

Taking little other than common cuticle, loaded with a small amount of melanin, butterflies have evolved some stunning microstructures in their wing scales. These structured surfaces, often only microns thick, act as selective reflectors and polarizers as well as being sometimes very strong scatterers (white) or very strong absorbers (black) of electromagnetic radiation. This use of structure in nature to give striking effects when interacting with visible radiation is limited to dielectrics. When it comes to synthetic structures we may also use metals. Structured metals can also lead to unexpected effects such as negative index materials, perfect lensing and ‘cloaking’. Even at very long wavelengths (microwaves and beyond) where metals are expected to behave as almost perfect mirrors they can be structured to be almost perfect absorbers. This talk will illustrate briefly the wonderful structural colours of butterflies focusing primarily on some recent developments in the physics of structured metals for use at microwave frequencies.

This talk is part of the Cavendish Physical Society series.

This talk is included in these lists:

• All Cavendish Laboratory Seminars
• All Talks (aka the CURE list)
• Cavendish Physical Society
• Centre for Health Leadership and Enterprise
• Cosmology, Astrophysics and General Relativity
• Featured lists
• Hanchen DaDaDash
• Inference Group Summary
• ME Seminar
• NanoDTC Energy Materials Talks
• NanoDTC Talks
• Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
• Pippard Lecture Theatre, Cavendish Laboratory
• School of Physical Sciences
• Thin Film Magnetic Talks

Note that ex-directory lists are not shown.