LENS/CMP Seminar
October 2, 2015
Speaker:
Tami Pereg-Barnea, McGill University
Title:
“Topological superconductivity from interactions”
Abstract:
The discussion of topology in condensed matter led to a paradigm shift – when
classifying states of matter, one needs to consider both the symmetry and the topology of
the system. In superconductivity this leads to an exciting result – a topological
superconductor capable of localizing a Majorana fermion, a peculiar excitation that is its
own antiparticle and may be useful for quantum computing.
Some encouraging evidence of topological superconductivity has been found
experimentally in one dimension when Majorana fermions reside on the edges of the
system. In two dimensions, many theoretical proposals have been found but the 2d
topological superconductor has not yet seen conclusively.
In this talk I will give an example of a model in which superconductivity arises from
interaction and may be topological when spin-orbit coupling is strong enough. The
topological state is induced when a Zeeman field is applied. I will also discuss the
characterization of topological states through their entanglement entropy.