Dynamics of long-living excitons in tunable potential landscapes

A novel method to experimentally study the dynamics of long-living excitons in coupled quantum well semiconductor heterostructures is presented. Lithographically defined top gate electrodes imprint in-plane artificial potential landscapes for excitons via the quantum confined Stark effect. Excitons are shuttled laterally in a time-dependent potential landscape defined by an interdigitated gate structure. Long-range drift exceeding a distance of 150μm at an exciton drift velocity vd≳103m/s is observed in a gradient potential formed by a resistive gate stripe.