Intrinsic charge transfer in mixed halide compounds PtX_(x)X'_(1-x ) was studied in the framework of the two-band extended Pielerls-Hubbard model.It was found that the number of transferred charges can be a fracti...Intrinsic charge transfer in mixed halide compounds PtX_(x)X'_(1-x ) was studied in the framework of the two-band extended Pielerls-Hubbard model.It was found that the number of transferred charges can be a fraction times of the electronic charge.The maximum amount of the transferred charges will occur at a certain proportion x for a given mixed compound.展开更多
Based on the non-equilibrium Green’s method and density functional theory,we investigate the electronic trans-port properties of ternary heterostructures based on carbon nanotubes and boron nitride nanotubes,with dif...Based on the non-equilibrium Green’s method and density functional theory,we investigate the electronic trans-port properties of ternary heterostructures based on carbon nanotubes and boron nitride nanotubes,with different atomic compositions,coupled to gold electrodes.Negative differential resistance(NDR)behavior can be observed due to suppression of the conduction channel at a certain bias.More importantly,the position of NDR can be tuned into the bias range as low as tens of meV by increasing the length of boron nitride nanotube.The peak-to-valley ratio,which is a typical character of NDR behavior,is also sensitive to the atomic compositions.展开更多
The electronic transport properties of a kind of phenylacetylene compound(4-mercaptophenyl)-phenylacetylene(MPPA)are studied by the first-principles method.A dithiocarboxylate conjugated linker(–CS_(2))is used to anc...The electronic transport properties of a kind of phenylacetylene compound(4-mercaptophenyl)-phenylacetylene(MPPA)are studied by the first-principles method.A dithiocarboxylate conjugated linker(–CS_(2))is used to anchor the molecule to one gold electrode.Rectification behavior is observed,which is mainly brought about by the asymmetrical coupling of electrodes to the molecule.There is a drastic increase in current as the electrode-electrode distance is reduced,and the rectification ratio increases by 40%as the electrode-electrode distance is diminished from 16Åto 15.7Å.For comparison,we also perform simulations with the–CS_(2) linker replaced by thiol linkage.It shows an obvious reduction in current.We find that the stronger interface coupling induced by the–CS_(2) linker broadens transmission resonances near the Fermi energy,which leads to the current enhancement of the molecular junction with–CS_(2) linker.展开更多
Based on nonequilibrium Green's function method and density functional theory calculations,we investigate theoretically the electronic transport properties of 1,4-bis(fullero[c]pyrrolidinl-yl)benzene (BDC60).A low...Based on nonequilibrium Green's function method and density functional theory calculations,we investigate theoretically the electronic transport properties of 1,4-bis(fullero[c]pyrrolidinl-yl)benzene (BDC60).A low bias negative differential resistance with the peak-to-valley ratio as high as 305.41 is obtained.The observed negative differential resistance is explained in terms of the evolution of the transmission spectra,molecular projected self-consistent Hamiltonian states and molecular projected energy levels with applied bias.展开更多
基金Supported by the Doctoral Foundation of the National Education Committee of China。
文摘Intrinsic charge transfer in mixed halide compounds PtX_(x)X'_(1-x ) was studied in the framework of the two-band extended Pielerls-Hubbard model.It was found that the number of transferred charges can be a fraction times of the electronic charge.The maximum amount of the transferred charges will occur at a certain proportion x for a given mixed compound.
基金Supported by the National Natural Science Foundation of China under Grant No 11104115the Natural Science Foundation of Shandong Province under Grant No ZR2009AL004the Doctoral Foundation of University of Jinan under Grant No XBS1004.
文摘Based on the non-equilibrium Green’s method and density functional theory,we investigate the electronic trans-port properties of ternary heterostructures based on carbon nanotubes and boron nitride nanotubes,with different atomic compositions,coupled to gold electrodes.Negative differential resistance(NDR)behavior can be observed due to suppression of the conduction channel at a certain bias.More importantly,the position of NDR can be tuned into the bias range as low as tens of meV by increasing the length of boron nitride nanotube.The peak-to-valley ratio,which is a typical character of NDR behavior,is also sensitive to the atomic compositions.
基金Supported by the Special Funds of the National Natural Science Foundation of China under Grant No 11074146the Jining University Research Program(No 2011YYJJ09).
文摘The electronic transport properties of a kind of phenylacetylene compound(4-mercaptophenyl)-phenylacetylene(MPPA)are studied by the first-principles method.A dithiocarboxylate conjugated linker(–CS_(2))is used to anchor the molecule to one gold electrode.Rectification behavior is observed,which is mainly brought about by the asymmetrical coupling of electrodes to the molecule.There is a drastic increase in current as the electrode-electrode distance is reduced,and the rectification ratio increases by 40%as the electrode-electrode distance is diminished from 16Åto 15.7Å.For comparison,we also perform simulations with the–CS_(2) linker replaced by thiol linkage.It shows an obvious reduction in current.We find that the stronger interface coupling induced by the–CS_(2) linker broadens transmission resonances near the Fermi energy,which leads to the current enhancement of the molecular junction with–CS_(2) linker.
基金Supported by the National Natural Science Foundation of China under Grant No 11104115the Natural Science Foundation of Shandong Province under Grant No ZR2009AL004+1 种基金the Doctoral Foundation of University of Jinan under Grant No XBS1004the Key Laboratory of Semiconductor Materials Science Program of Institute of Semiconductors of Beijing under Grant No KLSMS-0908.
文摘Based on nonequilibrium Green's function method and density functional theory calculations,we investigate theoretically the electronic transport properties of 1,4-bis(fullero[c]pyrrolidinl-yl)benzene (BDC60).A low bias negative differential resistance with the peak-to-valley ratio as high as 305.41 is obtained.The observed negative differential resistance is explained in terms of the evolution of the transmission spectra,molecular projected self-consistent Hamiltonian states and molecular projected energy levels with applied bias.
