فهرست

اثر هندسه‌ی تماس بر رفتار جریان -ولتاژ در اتصالات تک-مولکولی

نشریه: سال دوم-شماره3-پاییز 1394 - مقاله 2   صفحات :  125 تا 129



کد مقاله:
nm-141

مولفین:
سعیده رمضانی اکبر اباد: دانشگاه گیلان - گروه فیزیک
حمید رحیم پور سلیمانی


چکیده مقاله:

در این مقاله، ترابرد الکترون در یک سیستم مولکولی فلز/مولکول/فلز شامل مولکول بای فنیل دی سیئول و الکترودهای طلا، برای سه هندسه‌ی اتصال مختلف بررسی شده است. در این پژوهش هامیلتونی مولکول با استفاده از روش هاکل محاسبه شده است. فرمول¬بندی مورد استفاده بر پایه روش تابع گرین غیرتعادلی و در چارچوب فرمول¬بندی لاندائو و بوتیکر می¬باشد. نمودارهای ضریب عبور و جریان-ولتاژ، برای سه ساختار هندسی گوناگون محاسبه شده است. نتایج نشان می¬دهند که انتقال الکترون به شدت تحت تاثیر اثر تداخل کوانتومی امواج گذرنده و هندسه فصل مشترک مولکول و الکترودها است. دامنه جریان در حالت متقارن بیش¬تر از دو حالت¬¬ غیرمتقارن می¬باشد که دلیل این امر اثر تداخل کوانتومی امواج الکترونی گذرنده از شاخه¬های گوناگون مولکول است.


Article's English abstract:

In this paper, electron transport in a metal/molecule/metal molecular system Includes biphenyl-dithiol molecule and three-dimensional gold electrodes for three different types of contact geometry, are investigated. The Hamiltonian of the molecule is calculated based on the Hückel method and the current is computed by the non-equilibrium Green’s function method in the framework of Landauer–Büttiker formalism. Transmission coefficient and current-voltage characteristics are calculated for three different geometric structures. The results show that electron transport is strongly affected by quantum interference of electron waves and the geometry of the molecule-electrode interface. The current amplitude for symmetric coupling is larger than two other asymmetric couplings because of the quantum interference effects of the electron waves traveling through the different paths.


کلید واژگان:
اتصالات مولکولی، تابع گرین غیرتعادلی، نظریه هاکل گسترش یافته، هندسه اتصالات.

English Keywords:
Molecular junctions, Extended Huckel theory, Non-equilibrium Green’s function, Junction geometry.

منابع:
ندارد

English References:
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