Current-induced dynamics in carbon atomic contacts

• Jing-Tao Lü,
• Tue Gunst,
• Per Hedegård and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2011, 2, 814–823, doi:10.3762/bjnano.2.90

• applied between the two electrodes, Vb. We will show that this offers a convenient way to explore current-induced vibrational instabilities. We can already see the effect of the gate potential in the current–voltage (I − Vb) characteristics shown in Figure 2. The effect of the NC and BP forces is to

• perpendicular to the graphene surface. The center panel shows the calculated contour plot of the electrostatic-potential drop across the junction at Vg = 0 V, and Vb = 1 V. The equal drop at the left and right electrodes reflects the electron–hole symmetry for Vg = 0 V [40]. Current–Voltage (I−Vb) curves at

Nonconservative current-induced forces: A physical interpretation

• Tchavdar N. Todorov,
• Daniel Dundas,
• Anthony T. Paxton and
• Andrew P. Horsfield

Beilstein J. Nanotechnol. 2011, 2, 727–733, doi:10.3762/bjnano.2.79

• –electron interactions, determine the current–voltage spectrum of the system. Allowing nuclei to respond to current-induced forces introduces two additional elements: Current-driven displacements and Joule heating. Current-induced forces arise, fundamentally, through momentum transfer from the electron flow

Charge transport in a zinc–porphyrin single-molecule junction

• Mickael L. Perrin,
• Christian A. Martin,
• Ferry Prins,
• Ahson J. Shaikh,
• Rienk Eelkema,
• Jan H. van Esch,
• Jan M. van Ruitenbeek,
• Herre S. J. van der Zant and
• Diana Dulić

Beilstein J. Nanotechnol. 2011, 2, 714–719, doi:10.3762/bjnano.2.77

• allows us to characterize the transport in a molecular junction in detail. This complex molecule can form different junction configurations, having an observable effect on the trace histograms and the current–voltage (I(V)) measurements. Both methods show that multiple, stable single-molecule junction

• (MCBJ) technique, we study the low-bias conductance as a function of the electrode displacement. In addition, we perform current–voltage measurements at different electrode spacings in order to gain spectroscopic information in the high-bias regime. The MCBJ technique is an elegant way to control the

• low-bias conductance of the molecule as a function of the electrode stretching. Second, we perform spectroscopy of the molecular energy levels by measuring current–voltage characteristics at fixed electrode spacings; this was done both at room temperature and cryogenic temperature (6 K). Results To

An MCBJ case study: The influence of π-conjugation on the single-molecule conductance at a solid/liquid interface

• Wenjing Hong,
• Hennie Valkenier,
• Gábor Mészáros,
• David Zsolt Manrique,
• Artem Mishchenko,
• Alexander Putz,
• Pavel Moreno García,
• Colin J. Lambert,
• Jan C. Hummelen and
• Thomas Wandlowski

Beilstein J. Nanotechnol. 2011, 2, 699–713, doi:10.3762/bjnano.2.76

• current–distance and current–voltage measurements revealed details of the influence of π-conjugation on the single-molecule conductance. Keywords: anthraquinone; π-conjugation; mechanically controlled break junction; single-molecule conductance; Introduction Molecular electronics has expanded

• ), and a dihydroanthracene-based wire with a broken π-conjugation (AH) (Figure 1). The transport characteristics in single molecular junctions were investigated by conductance–distance as well as continuous current–voltage measurements in complementary MCBJ and STM-BJ experiments. In particular, a custom

• same analysis method to the blue traces did not lead to any clear feature between 10−1 G0 and 10−8 G0, which supports the assignment of the two types of traces. Continuous current–voltage (I–V) measurement I–V curves in the stretching process The high mechanical stability of the MCBJ setup provides a

Charge transfer through single molecule contacts: How reliable are rate descriptions?

• Denis Kast,
• L. Kecke and
• J. Ankerhold

Beilstein J. Nanotechnol. 2011, 2, 416–426, doi:10.3762/bjnano.2.47

• molecule, i.e., with Single charge tunneling through the device can be formally and exactly captured under weak conditions (e.g., instantaneous equilibration in the leads during charge transfer) within the Meir–Wingreen formulation based on nonequilibrium Green’s functions [14][15]. For the current

• –voltage characteristics one finds with energy dependent lead self-energies ∑α(ε) = 2π∑k|Tk,α|2δ(ε – εk) and with the Fourier transforms of the time dependent Green’s functions and . Upon applying the polaron transformation (Equation 2), one has where all expectation values are calculated with the full