Conductance Oscillations in a Quantum Wire with a Stub Structure due to Quantum Interference

Abstract

Y-shaped structures of a quantum wire with a stub were fabricated in a split gate configuration. Periodic oscillations in the conductance versus split gate voltage curve were observed for the Y-shaped structure of a quantum wire with a stub. In contrast, aperiodic conductance oscillations were observed in a Y-shaped branch in which the reflection wall in the stub had been removed. The distinct difference between the characteristics of these structures suggests that the observed periodic oscillations were caused by quantum interference in the stub. In addition, the calculated gate voltage period based on a model that attributes conductance oscillations to quantum interference in the stub is in good agreement with the experimental period.