Are transport anomalies in ‘‘electron waveguides’’ classical?

Abstract

We test the implicit prediction of a recent classical model that transport anomalies in ballistic multiprobe conductors—the last plateau, quenching, and the negative bend resistance—should scale with Fermi momentum, ${\mathit{p}}_{\mathit{F}}$. Data from junctions defined by adiabatic lateral potentials (having corners with radii of curvature ${\mathit{r}}_{\mathit{J}}$>ħ/${\mathit{p}}_{\mathit{F}}$) qualitatively scale classically; departures observed are attributed to momentum-memory loss from random scattering. With more abrupt (square-cornered) junctions, however, nonclassical ${\mathit{p}}_{\mathit{F}}$ dependence emerges.