Highly symmetric and tunable tunnel couplings in InAs/InP nanowire heterostructure quantum dots

  title={Highly symmetric and tunable tunnel couplings in InAs/InP nanowire heterostructure quantum dots},
  author={Frederick S Thomas and Andreas Baumgartner and Lukas Gubser and Christian J{\"u}nger and Gergő F{\"u}l{\"o}p and Malin Nilsson and Francesca Rossi and Valentina Zannier and Lucia Sorba and Christian Schoenenberger},
We present a comprehensive electrical characterization of an InAs/InP nanowire (NW) heterostructure, comprising of two InP barriers forming a quantum dot (QD), two adjacent lead segments and two metallic contacts. We demonstrate how to extract valuable quantitative information of the QD. The QD shows very regular Coulomb blockade resonances over a large gate voltage range. By analyzing the resonance line shapes, we map the evolution of the tunnel couplings from the few to the many electron… 

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