Tip-contact related low-bias negative differential resistance and rectifying effects in benzene-porphyrin-benzene molecular junctions.
The electronic transport properties of benzene-porphyrin-benzene (BPB) molecules coupled to gold (Au) electrodes were investigated. By successively removing the front-end Au atoms, several BPB junctions with different molecule-electrode contact symmetries were constructed. The calculated current-voltage (I-V) curves depended strongly on the contact configurations between the BPB molecules and the Au electrodes. In particular, a significant low-voltage negative differential resistance effect appeared at -0.3 V in the junctions with pyramidal electrodes on both sides. Along with the breaking of this tip-contact symmetry, the low-bias negative differential resistance effect gradually disappeared. This tip-contact may be ideal for use in the design of future molecular devices because of its similarity with experimental processes.
College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Jue-Fei
JF
Cheng
College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Liping
L
Zhou
College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Man
M
Liu
College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Qiang
Q
Yan
College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Qin
Q
Han
College of Physics, Optoelectronics and Energy and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
Lei
L
Gao