Conductance

About: Conductance is a research topic. Over the lifetime, 8088 publications have been published within this topic receiving 235961 citations.

Conductance quantization above 30 K in GaAlAs shallow-etched quantum point contacts smoothly joined to the background 2DEG

Abstract: The electrical characteristics of shallow etched GaAs/GaAlAs quantum point contacts (QPCs) of various shapes have been studied as a function of temperature above 0.3 K. Quantized conductance was observed up to 36 K, and from the temperature dependence of the conductance staircase we find energy separations between the lowest one-dimensional subbands up to 20 meV. This value exceeds the highest values so far reported for laterel QPC constrictions in GaAs/GaAlAs heterostructures. In addition, very well behaved quantized conductance plateaus were observed at the lowest temperatures.

Strong Tunneling in the Single-Electron Transistor

Abstract: We have investigated the suppression of single-electron charging effects in metallic single-electron transistors when the conductance of the tunnel junctions becomes larger than the conductance quantum ${e}^{2}/h$. We find that the Coulomb blockade of the conductance is progressively shifted at lower temperatures. The experimental results agree quantitatively with the available $1/T$ expansion at high temperature, and qualitatively with the predictions of an effective two-state model at low temperature, which predicts at $T\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ a blockade of conductance for all gate voltages.

Temperature Dependence of Conductance of Electrolytes in Nonaqueous Solutions

Abstract: All equations in this chapter can be used either with SI or cgs units.1 For this purpose, appropriate physical constants and conversion factors are summarized in Table 1. Concentration c is used throughout at mol liter−1. This requires a conversion factor 10 n with n(SI)=+3; n(cgs)=−3.

Afterhyperpolarization conductance time course in lumbar motoneurones of the cat.

Abstract: The time and potential dependence of the conductance process (es) underlying the longlasting afterhyperpolarization (AHP) in the cat's a-motoneurones were studied. The conductance changes were determined by injection of short current pulses. The conductance time course was characterized by a longlasting exponential decay interrupted by a plateau corresponding to the slower hypcrpolarizing phase of the AHP. By displacing the membrane potential in the subthreshold region with the injection of longlasting current pulses it was found that the conductance was largely unaffected by membrane potential displacements. Similar characteristics were found when calculating the AHP conductance time course from the AHP voltage. It was concluded that the AHP in motoneurones is given by a potassium conductance process with this complex S-shaped time course. A mathematical expression describing this time course is given.

Solvent Dependence of the Single Molecule Conductance of Oligoyne-Based Molecular Wires

Abstract: The conductance and the decay of conductance as a function of molecular length within a homologous series of oligoynes, Me3Si—(C≡C)n—SiMe3 (n = 2, 3, 4, or 5), is shown to depend strongly on the solvent medium. Single molecule junction conductance measurements have been made with the I(s) method for each member of the series Me3Si—(C≡C)n—SiMe3 (n = 2, 3, 4, and 5) in mesitylene (MES), 1,2,4-trichlorobenzene (TCB), and propylene carbonate (PC). In mesitylene, a lower conductance is obtained across the whole series with a higher length decay (β ≈ 1 nm–1). In contrast, measurements in 1,2,4-trichlorobenzene and propylene carbonate give higher conductance values with lower length decay (β ≈ 0.1 and 0.5 nm–1 respectively). This behavior is rationalized through theoretical and computational investigations, where β values are found to be higher when the contact Fermi energies are close to the middle of the HOMO–LUMO gap but decrease as the Fermi energies approach resonance with either the occupied or unoccupied ...