Quantum Information Seminar Series: Netanel Lindner

  • Date: 03/09/2011
Netanel Lindner

University of British Columbia


Putting Floquet theory to work: Topology of time dependent Hamiltonians


Topological phases of matter have captured our imagination over the past
few years, with tantalizing properties such as robust edge modes and
exotic non-Abelian excitations, and potential applications ranging from
semiconductor spintronics to topological quantum computation. Despite
recent advancements in the field, our ability to control topological
transitions remains limited, and usually requires changing material or
structure properties. We show that a topological state can be induced in
a semiconductor quantum well, initially in the trivial phase, by
irradiation with microwave frequencies, without changing the well
structure, closing the gap and crossing the phase transition. We show
that the quasi-energy spectrum exhibits a single pair of helical edge
states. We discuss the necessary experimental parameters for our
proposal. This proposal provides an example and a proof of principle of a
new non-equilibrium topological state: a "Floquet topological