Charge transport through a semiconductor quantum dot-ring nanostructure

Abstract

Transport properties of a gated nanostructure depend crucially on the coupling of its states to the states of electrodes. In the case of a single quantum dot the coupling, for a given quantum state, is constant or can be slightly modified by additional gating. In this paper we consider a concentric dot-ring nanostructure (DRN) and show that its transport properties can be drastically modified due to the unique geometry. We calculate the dc current through a DRN in the Coulomb blockade regime and show that it can efficiently work as a single electron transistor or a current rectifier. In both cases the transport characteristics strongly depends on the details of the confinement potential. The calculations are carried out for low and high bias regime, the latter being especially interesting in the context of current rectification due to fast relaxation processes.

24 pages, 13 figure

References in corpus (10)

• Chaotic Dirac billiard in graphene quantum dots
• Single-shot read-out of an individual electron spin in a quantum dot
• Driven coherent oscillations of a single electron spin in a quantum dot
• Spin qubits in graphene quantum dots
• Persistent currents in normal metal rings
• Observation of strongly entangled photon pairs from a nanowire quantum dot
• Quantum dot as thermal rectifier
• Orbital and spin relaxation in single and coupled quantum dots
• Semiconductor quantum ring as a solid-state spin qubit
• Wave function engineering in quantum dot-ring nanostructures