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Novel devices for measuring interactions in quantum point contacts
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TLDR
In this paper, the authors performed measurements on two new kinds of devices which give new insight into the interactions of electrons in these clean quasi-lD systems, and measured the compressibility of the electrons in a QPC for different conduction modes.Abstract:
Conductance measurements of quantum point contacts (QPCs) reveal an anomalous plateau in the conductance at roughly 0.7 x ^ , just before a fully transmitting ID channel is available. Past experiments have built a consensus that this so-called "0.7 structure" is related to electron spin and electron-electron interaction, but the detailed description remains controversial. We have performed measurements on two new kinds of devices which give new insight into the interactions of electrons in these clean quasi-lD systems. One new device allows us to measure the compressibility of the electrons in a QPC for different conduction modes. Comparison with density functional calculations give new information about the relative importance of interactions (including exchange) as the density in the QPC is depleted. The other device allows us to measure the local density of states (dos) in the QPC as we tunnel directly into the constriction. Deviations from the ID dos would help to develop a more complete picture of the transport through a QPC.read more
Citations
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Kondo Effect in a Single Electron Transistor
TL;DR: Goldhaber-Gordon et al. as mentioned in this paper used nanofabrication to construct a spin singlet state between the unpaired localized electron and delocalized electrons at low temperatures.
Conductance of a quantum wire in the Wigner crystal regime
TL;DR: The effect of Coulomb interactions on the conductance of a single-mode quantum wire connecting two bulk leads when the density of electrons in the wire is very low, they arrange in a finite-length Wigner crystal is studied.
Posted Content
Interaction Effects at Crossings of Spin-Polarised One-Dimensional Subbands
A. C. Graham,Kalarikad Thomas,Michael Pepper,Nigel R. Cooper,Michelle Y. Simmons,D. A. Ritchie +5 more
TL;DR: In this paper, conductance measurements of ballistic one-dimensional (1D) wires defined in GaAs/AlGaAs heterostructures in an in-plane magnetic field are reported.
References
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