Condensed Matter seminars

A geometric construction of topological invariants for crystals with time-reversal symmetry

Name: A geometric construction of topological invariants for crystals with time-reversal symmetry
Start: 2017-09-13T15:30:00+02:00
End: 2017-09-13T16:30:00+02:00
Location: No location set

by Krzysztof Gawedzki (ENS de Lyon)

Wednesday 13 Sept 2017, 15:30 → 16:30 Europe/Stockholm

Nordita South

Description

I shall discuss a construction of Z_2-valued invariants of topological phases for 2d and 3d time-reversal symmetric crystals, both static and periodically driven. The construction uses a geometric structure (a gerbe) on U(N) that encodes ambiguities of the logarithm of a unitary matrix.