Pascal conductance series in ballistic one-dimensional LaAlO ₃ /SrTiO ₃ channels

Abstract

An unusual conductance sequence Effects of correlations between electrons are enhanced in systems of reduced dimensions. The two-dimensional interface between two oxide materials, lanthanum aluminate (LaAlO 3 ) and strontium titanate (SrTiO 3 ), exhibits magnetism and superconductivity. In even lower-dimensional systems fabricated in similar heterostructures, electrons can pair without going superconducting. Briggeman et al. have now observed another exotic effect in LaAlO 3 /SrTiO 3 waveguides: At certain magnetic fields, the conductance in these one-dimensional systems exhibits steps of an unconventional sequence. To understand the experimental data, the researchers used a model that accounted for interactions between electrons and found that the phenomenology was consistent with the formation of a series of correlated phases characterized by bound states of three or more electrons. Science , this issue p. 769