New directions for intergroup meetings

Tom Lancaster

• We’re hoping to make talks more accessible, wide-ranging and interesting

• Less emphasis on technical descriptions of your most recent results

• Talks can be introductory, speculative, provocative and outside the immediate field of materials physics.

What are we trying to do?

Particular suggestions

Journal club: a discussion of a scientific paper

Topical physics: ideas from across physics needed to understand something in your field

Personal hobby-horse: be it cookery, rocketry, electronics, music…

Discussion and debates

Please submit talk titles in advance

• If something looks too inaccessible, we’ll ask you to think again

• Please don’t be offended!

Suggestions box

If you have something you’d like someone to talk about send an email to chairs or to

tom.lancaster@durham.ac.uk

Journal club talks

Pick a paper. Nature, Science, PRL, historically important

Paper by L D Landau, JEPT 30, 1058 (1956)

Describes a new, phenomenological model of metals

Context and background

• What problem is being discussed? • Why is this important?• Who is writing the paper?

The fermi gas treats electrons as non-interacting

It describes metals very well, but it shouldn’t

Electrons interact very strongly – is there a better way?

Lev Landau invented much of condensed matter physics, his answer to this question caused a revolution.

What’s in the paper

• What are the important results described?

• What do the authors conclude?

Fermi liquid made of quasiparticles – one for each electron

Excitations are unstable, but the ones near the Fermi energy live the longest

Landau’s expansion of the energy allows him to describe the system withonly a few parameters

What do you think of the paper?

• Are the results convincing?• Can someone else do better• Keep literary criticism to a minimum!

What do you think of the paper?

• Are the results convincing?• Can someone else do better• Keep literary criticism to a minimum!

Early Chinese chemists could not have imagined two thousand years ago that BaCuSi2O6 was not only an attractive purple pigment but also a potential solid state device for exploring the quantum effects of a BEC at liquid 4He temperatures in magnetic fields. (PRL 93, 087203 (2004))

Landau’s paper is very sketchy – it’s hard to know what the big idea is

It turned out to be incredibly important – the standard model of CMP

It’s a work of genius!

Future work

• What next for this field?

• How does this paper fit into the grand scheme

Guide to talks

• Keep them short• Make it simple• Keep slides uncluttered• Everyone likes history, psychology, sociology…• Avoid length conclusions!

• See N D Mermin, Physics Today, November 1992, page 9.