Channel saturation and conductance quantization in single-atom gold constrictions

Abstract

Notwithstanding the discreteness of metallic constrictions, it is shown that the finite elasticity of stable, single-atom gold constrictions allows for a continuous and reversible change in conductance, thereby enabling observation of channel saturation and conductance quantization.The observed channel saturation and signature for conductance quantization is achieved by superposition of atomic/subatomic-scale oscillations on a retracting/approaching gold tip against a gold substrate of a scanning probe. Results also show that conductance histograms are neither suitable for evaluating the stability of atomic configurations through peak positions or peak height nor appropriate for assessing conductance quantization. A large number of atomic configurations with similar conductance values give rise to peaks in the conductance histogram.The positions of the peaks and counts at each peak can be varied by changing the conditions under which the histograms are made. Histogram counts below 1 cannot necessarily be assumed to arise from single-atom constrictions.1

The functional integral in the Hubbard model

“…Finally, we stress that the functional integral in the Hubbard model, as shown in this paper, can be successfully reformulated in terms of both the standard and the Jackson integral and that the latter can be reduced to the p-adic integral in a particular case. We have the impression (supported by the comparison with experimental data [4,5,6,7]) that in the strong correlation regime, the description of multi-electron systems is invariant under the choice of the number field. We can begin with either a p-adic or real number description.…”

“…A function of the typea i is symmetric with respect to its coordinates (bosonic type), while the functions b i , c i are skew-symmetric under coordinate interchanges (fermionic type). The general form of the functions | G > is expression (6), where the exponent has the form mn X mn φ mn ,and the functions φ mn are χ * k , h, E. Supercoherent state (6) determines the supergroup representation with the set of supergenerators X nm . We note that the expressions for the above supercoherent states were calculated exactly in [20].…”

“…Jumps of the conductivity and magnetization were observed in other systems and materials [4,5,6]. We proposed [8,9] describing such a behavior of macroscopic quantities using functions of the argument taking values in the p-adic number field.…”

О Функциональном Интеграле В Модели Хаббарда

“…В работе [4] для полимера TA-PPE (производная от poly(р-phenyleneethynylene) в зависимости проводимости от приложеного напряжения были обнаружены скачки двух типов -в виде ступенек и в виде пилы. Скачки проводимости и на-магниченности были обнаружены и в других системах и материалах [5]- [7]. В на-ших работах [8], [9] для описания такого типа поведения макроскопических величин 480 В. М. ЖАРКОВ было предложено использовать функции от аргумента, принимающего значения в поле -адических чисел.…”

Mechanics of quantum and Sharvin conductors

“…20,21,[27][28][29][30][31][32][33][34][35][36][37] Given that these atomic-scale devices are acutely sensitive to minute perturbations (electrical, thermal, magnetic, chemical, mechanical, etc. ), a fundamental understanding is needed on their mechanical stability, forces holding them together, and the ability to measure them.…”