Coulomb blockade regime

Mesoscopic physics has defined many of the issues (Landauer limit transport [10, 11], Coulomb blockade regime [12], Kondo resonance regime [13-15]...) that will occur later in this chapter describing molecular transport junctions. These concepts are relevant, but must be reinterpreted to understand the molecular case. 

Summary. The interplay between electrical and mechanical properties of suspended, doubly clamped carbon nanotubes in the Coulomb blockade regime is studied theoretically. In this geometry, the capacitance between the nanotube and the gate depends on the distance between them. We find that the tube position changes in discrete steps every time an electron tunnels onto it. Edges of Coulomb diamonds acquire a (small) curvature. Eigenffequencies are modified by Coulomb blockade in a discrete fashion. 

Since the nanotube is attached to the electrodes by tunneling contacts, it is in the Coulomb blockade regime. We define the energy to add the nth electron to the tube as Sn = Wn - Wn i. Then, if the nanotube contains n > 0 electrons, the conditions that current can not flow (is Coulomb blocked) are... 

The source and drain tunnel resistances and capacitances are assumed equal, the charging energy is 100 k T. For gate charge Qc = 0, the single-electron transistor is in the Coulomb blockade regime, and the l-Vcurve exhibits the... 

In mesoscopic physics, because the geometries can be controlled so well, and because the measurements are very accurate, current under different conditions can be appropriately measured and calculated. The models used for mesoscopic transport are the so-called Landauer/Imry/Buttiker elastic scattering model for current, correlated electronic structure schemes to deal with Coulomb blockade limit and Kondo regime transport, and charging algorithms to characterize the effects of electron populations on the quantum dots. These are often based on capacitance analyses (this is a matter of thinking style - most chemists do not consider capacitances when discussing molecular transport junctions). 

When the coupling to the leads is weak, electron-electron interaction results in Coulomb blockade, the sequential tunneling is described by the master equation method [169-176] and small cotunneling current in the blockaded regime can be calculated by the next-order perturbation theory [177-179], This theory was used successfully to describe electron tunneling via discrete... 

Contacts, 19-2-19-3, 19-6-19-10, 19-17, 19-19, 19-23-19-24, 19-29, 19-31, 19-39 Contour length, 9-24, 9-25-9-26 Conventional thin films, 7-20 Cooperativity, 18-7-18-8 Coplanarity, 9-23 Copolymerization, 8-13-8-14 Copolymers, 20-13, 20-22, 20-34-20-44 Core-excited states, 21-7 Corrosion, 18-6-18-7, 18-29 Cotton effect, 3-9-3-12 Coulomb blockade transport, 16-15-16-18 Coulomb-blockade (CB), 16-15-16-18, 16-21 Critical regime, 16-5, 16-9 Crossed metallic SWNT, 16-11 Cross-linking, 7-32, 7-34-7-35, 8-12-8-13, 8-34-8-38, 9-17, 9-18... 

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