Open AccessCalculation of the electronic transmission spectra of a molecular device using a simplified model
Author(s) -
Qiao-Hua Li,
Zhenhua Zhang,
Xinhai Liu,
Ming Qiu,
Ding Kai-He
Publication year - 2009
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.58.7204
Subject(s) - transmission coefficient , quantum tunnelling , materials science , transmission (telecommunications) , rectangular potential barrier , electron , spectral line , molecule , molecular physics , atomic physics , condensed matter physics , physics , optoelectronics , quantum mechanics , telecommunications , computer science
Based on the structural characteristics of a molecular wire coupled to electrodesthe electronic tunneling process in a molecular device consisting of such a composite molecule under a bias is modeled by a simplified successive tunneling model with asymmetric multiple potential barriers in series. An analytical expression for the electronic transmission spectrum is obtained. Thenthe relations between the transmission coefficient and various parameterssuch as the width and height of the barrierthe distance between two neighboring barriersthe effective mass of electron, and the bias voltage, are calculated. It is found that when the electron energies are equal to some special valuesobvious resonant tunneling occursand the transmission coefficient is very sensitive to the parameters mentioned above. The results presented here suggest that the transport behaviors of molecular electronic devices can be significantly modified in a controlled way, for exampleby altering the constituents or/and the configurations of the composite molecule.