Karyn Le Hur Wednesday, 09:35 - 10:05
Engineering Topological Mott Phases from Quantum Spin Chains with Majorana Fermions
With potential applications in quantum information and spintronics, topological order, topological insulators
and topological superconductors are currently in the center of interest of quantum physics. There is an on-going active search
for feasible realizations in and outside of solid-state systems. Experimentalists investigating ultracold atoms in optical
lattices and photons in artificial lattices have also made impressive steps towards simulating many-body physics,
artificial gauge fields and spin-orbit couplings using light-matter engineering.

In this talk, we introduce quantum spin chains by analogy to the solvable two-dimensional honeycomb Kitaev lattice model, and build
relations between p-wave superconductivity, Majorana states and Anderson RVB spin-liquid phases. We describe the physics of
such chains, as well as ladder systems, and show possible applications for quantum information (braiding of Majorana fermions and qubit states).
These systems constitute examples of topological Mott insulators, described by a charge gap, and topological spin properties
related to gapless Majorana fermions in the bulk and gapless spin-1/2 edge modes by analogy to spin-1 chains and the SSH model.
These systems also show an exact relation with BCS superconductivity. We discuss possible realisations of such spin chains.

Reference: Karyn Le Hur, Ariane Soret and Fan Yang 1703.07322