title: Confinement-deconfinement transition due to spontaneous symmetry breaking in quantum Hall bilayers.
abstract: Band-inverted electron-hole bilayers support quantum spin Hall insulator and exciton condensate phases. Interest in quantum spin Hall effect in these systems has recently put them in the spotlight. We investigate such a bilayer in an external magnetic field. We show that the interlayer correlations lead to formation of a helical quantum Hall exciton condensate state. Existence of the counterpropagating edge modes in this system results in formation of a ground state spin-texture not supporting gapless single-particle excitations. The charged edge excitations in a sufficiently narrow Hall bar are confined: a charge on one of the edges always gives rise to an opposite charge on the other edge. Magnetic field and gate voltages allow the control of a confinement-deconfinement transition of charged edge excitations, which can be probed with nonlocal conductance. Confinement-deconfinement transitions are of great interest, not least because of their possible significance in shedding light on the confinement problem of quarks.
authors.affiliation: Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1.|Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.|Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands.
authors.forename: D I
authors.initials: DI
authors.lastname: Pikulin
authors.affiliation: Institute for Mathematical Physics, TU Braunschweig, 38106 Braunschweig, Germany.
authors.forename: P G
authors.initials: PG
authors.lastname: Silvestrov
authors.affiliation: Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands.|Department of Physics and Nanoscience Center, P.O. Box 35 (YFL), FI-40014, University of Jyväskylä, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Hyart