Back Cover: Spin textures of strongly correlated spin Hall quantum dots (Phys. Status Solidi RRL 12/2013)

Abstract

When quantum confinement is applied to topological phases of matter, very interesting physics can emerge. Majorana fermions at the boundaries of topological superconductors are the most striking example. Another interesting system is a quantum dot defined into the edges of two-dimensional topological insulators. These edges represent a new state of matter, the helical Luttinger liquid, characterized by spin-momentum locking. In their work, Dolcetto et al. inspect the spin resolved charge density and the spin resolved density–density correlation functions of such quantum dots (see the Letter on pp. 1059–1063). The interplay between helicity and quantum confinement induced by magnetic barriers leads to strong oscillations in the spin resolved density even when Coulomb interaction is weak. The main finding is that when Coulomb interaction is strong, a peculiar spin texture emerges as signalled by the spin-resolved correlation functions. This crystal of spins is the counterpart of the charge Wigner crystal occurring in ordinary one-dimensional quantum dots.