Electromagnetism on ice : from quantum spin ice to protons in water ice

Datum

27.08.2015

Zeit

14:00 - 15:00

Sprecher

Nic Shannon

Zugehörigkeit

OIST

Sprache

en

Hauptthema

Physik

Andere Themen

Physik

Host

CMT seminars

Beschreibung

It has been known since the pioneering work of Bernal, Fowler and Pauling that hexagonal water ice is the architype of a frustrated material : a proton-bonded network in which protons satisfy strong local constraints - the "ice rules" - but do not order. Frustration of this type has been rediscovered many times since, in the context of charge order on pyrochlore lattice, proton-bonded ferroelectrics, models of polymer melts and, most famously, the family rare earth pyrochlore oxides known as "spin ice". Recently "quantum spin-ice" materials have attracted considerable attention as potential hosts for a quantum spin-liquid, in which the collective excitations of spins are described by a U(1) lattice gauge theory, and have the character of photons. In this talk we review some of the theoretical progress in understanding quantum spin ice, with emphasis on numerical results, and pose the question : should we be looking for a similar quantum liquid in the protons of water ice ? [1] O. Benton, O. Sikora and N. Shannon, arXiv:1504.04158

Letztmalig verändert: 27.08.2015, 09:37:52