Physics – Condensed Matter – Mesoscale and Nanoscale Physics
Scientific paper
2001-11-21
Phys. Rev. B 65, 165338 (2002) (fwd)
Physics
Condensed Matter
Mesoscale and Nanoscale Physics
17 pages, 4 figures, 1 Table; Expands cond-mat/0101126; Sec. VI on 2-contact setup added (Final version for PRB)
Scientific paper
10.1103/PhysRevB.65.165338
We investigate the charge fluctuations of a large quantum dot coupled to a two-dimensional electron gas via a quantum point contact following the work of Matveev. We limit our discussion to the case where exactly two channels enter the dot and we discuss the role of an anisotropy between the transmission coefficients (for these two channels) at the constriction. Experimentally, a channel-anisotropy can be introduced applying a relatively weak in-plane magnetic field to the system when only one ``orbital'' channel is open. The magnetic field leads to different transmission amplitudes for spin-up and spin-down electrons. In a strong magnetic field the anisotropic two-channel limit corresponds to two (spin-polarized) orbital channels entering the dot. The physics of the charge fluctuations can be captured using a mapping on the channel-anisotropic two-channel Kondo model. For the case of weak reflection at the point contact this has already briefly been stressed by one of us in PRB {\bf 64}, 161302R (2001). This mapping is also appropriate to discuss the conductance behavior of a two-contact set-up in strong magnetic field. Here, we elaborate on this approach and also discuss an alternative solution using a mapping on a channel-isotropic Kondo model. In addition we consider the limit of weak transmission. We show that the Coulomb-staircase behavior of the charge in the dot as a function of the gate voltage, is already smeared out by a small channel-anisotropy both in the weak- and strong transmission limits.
Hur Karyn Le
Seelig Georg
No associations
LandOfFree
Capacitance of a quantum dot from the channel-anisotropic two-channel Kondo model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Capacitance of a quantum dot from the channel-anisotropic two-channel Kondo model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Capacitance of a quantum dot from the channel-anisotropic two-channel Kondo model will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-341321