PIN ICE: "Monopoles", "Magnetricity" and "Magnetolytes

Date

Mar 9, 2011

Time

10:30 AM - 11:30 AM

Speaker

Prof. Steven Bramwell

Affiliation

London Centre for Nanotechnology, University College London, UK

Language

en

Main Topic

Physik

Other Topics

Chemie, Physik

Host

Prof. Dr. L. H. Tjeng

Description

The analogy between spin configurations in spin ice materials like Ho2Ti2O7 and proton configurations in water ice, H2O, has been appreciated for many years (see Bramwell and Gingras, Science, 294, 1495, 2001). However it is only in the last few years that this equivalence has been extended into the realm of electrodynamics. In this talk I shall describe our recent experimental work that identifies magnetic charges ("monopoles"), transient magnetic currents ("magnetricity") and the universal properties expected of an ideal magnetic Coulomb gas (magnetic electrolyte - "magnetolyte"). These universal properties include the Onsager-Wien effect, "corresponding states" behaviour, Debye-Huckel screening and Bjerrum pairing. I will describe experimental results for both traditional spin ice materials (Ho2Ti2O7, Dy2Ti2O7) and recently discovered systems (Dy2Ge2O7).

Last modified: Mar 7, 2011, 6:01:20 PM