Electron transport in real time from first-principles
While the vast majority of calculations reported on molecular conductance have been based on the static non-equilibrium Green’s function formalism combined with density functional theory (DFT), in recent years a few time-dependent approaches to transport have started to emerge. Among these, the driv...
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todo:paper_00219606_v146_n4_p_Morzan2023-10-03T14:24:37Z Electron transport in real time from first-principles Morzan, U.N. Ramírez, F.F. González Lebrero, M.C. Scherlis, D.A. Bins Calculations Current voltage characteristics Dynamics Electron transport properties Equations of motion Quantum theory Current voltage curve Gaussian basis functions Initial perturbation Molecular conductance Quantum dynamics simulation Semi-empirical methods Tight-binding calculations Unsaturated hydrocarbons Density functional theory While the vast majority of calculations reported on molecular conductance have been based on the static non-equilibrium Green’s function formalism combined with density functional theory (DFT), in recent years a few time-dependent approaches to transport have started to emerge. Among these, the driven Liouville-von Neumann equation [C. G. Sánchez et al., J. Chem. Phys. 124, 214708 (2006)] is a simple and appealing route relying on a tunable rate parameter, which has been explored in the context of semi-empirical methods. In the present study, we adapt this formulation to a density functional theory framework and analyze its performance. In particular, it is implemented in an efficient all-electron DFT code with Gaussian basis functions, suitable for quantum-dynamics simulations of large molecular systems. At variance with the case of the tight-binding calculations reported in the literature, we find that now the initial perturbation to drive the system out of equilibrium plays a fundamental role in the stability of the electron dynamics. The equation of motion used in previous tight-binding implementations with massive electrodes has to be modified to produce a stable and unidirectional current during time propagation in time-dependent DFT simulations using much smaller leads. Moreover, we propose a procedure to get rid of the dependence of the current-voltage curves on the rate parameter. This method is employed to obtain the current-voltage characteristic of saturated and unsaturated hydrocarbons of different lengths, with very promising prospects. © 2017 Author(s). Fil:Morzan, U.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:González Lebrero, M.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00219606_v146_n4_p_Morzan |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Bins Calculations Current voltage characteristics Dynamics Electron transport properties Equations of motion Quantum theory Current voltage curve Gaussian basis functions Initial perturbation Molecular conductance Quantum dynamics simulation Semi-empirical methods Tight-binding calculations Unsaturated hydrocarbons Density functional theory |
| spellingShingle |
Bins Calculations Current voltage characteristics Dynamics Electron transport properties Equations of motion Quantum theory Current voltage curve Gaussian basis functions Initial perturbation Molecular conductance Quantum dynamics simulation Semi-empirical methods Tight-binding calculations Unsaturated hydrocarbons Density functional theory Morzan, U.N. Ramírez, F.F. González Lebrero, M.C. Scherlis, D.A. Electron transport in real time from first-principles |
| topic_facet |
Bins Calculations Current voltage characteristics Dynamics Electron transport properties Equations of motion Quantum theory Current voltage curve Gaussian basis functions Initial perturbation Molecular conductance Quantum dynamics simulation Semi-empirical methods Tight-binding calculations Unsaturated hydrocarbons Density functional theory |
| description |
While the vast majority of calculations reported on molecular conductance have been based on the static non-equilibrium Green’s function formalism combined with density functional theory (DFT), in recent years a few time-dependent approaches to transport have started to emerge. Among these, the driven Liouville-von Neumann equation [C. G. Sánchez et al., J. Chem. Phys. 124, 214708 (2006)] is a simple and appealing route relying on a tunable rate parameter, which has been explored in the context of semi-empirical methods. In the present study, we adapt this formulation to a density functional theory framework and analyze its performance. In particular, it is implemented in an efficient all-electron DFT code with Gaussian basis functions, suitable for quantum-dynamics simulations of large molecular systems. At variance with the case of the tight-binding calculations reported in the literature, we find that now the initial perturbation to drive the system out of equilibrium plays a fundamental role in the stability of the electron dynamics. The equation of motion used in previous tight-binding implementations with massive electrodes has to be modified to produce a stable and unidirectional current during time propagation in time-dependent DFT simulations using much smaller leads. Moreover, we propose a procedure to get rid of the dependence of the current-voltage curves on the rate parameter. This method is employed to obtain the current-voltage characteristic of saturated and unsaturated hydrocarbons of different lengths, with very promising prospects. © 2017 Author(s). |
| format |
JOUR |
| author |
Morzan, U.N. Ramírez, F.F. González Lebrero, M.C. Scherlis, D.A. |
| author_facet |
Morzan, U.N. Ramírez, F.F. González Lebrero, M.C. Scherlis, D.A. |
| author_sort |
Morzan, U.N. |
| title |
Electron transport in real time from first-principles |
| title_short |
Electron transport in real time from first-principles |
| title_full |
Electron transport in real time from first-principles |
| title_fullStr |
Electron transport in real time from first-principles |
| title_full_unstemmed |
Electron transport in real time from first-principles |
| title_sort |
electron transport in real time from first-principles |
| url |
http://hdl.handle.net/20.500.12110/paper_00219606_v146_n4_p_Morzan |
| work_keys_str_mv |
AT morzanun electrontransportinrealtimefromfirstprinciples AT ramirezff electrontransportinrealtimefromfirstprinciples AT gonzalezlebreromc electrontransportinrealtimefromfirstprinciples AT scherlisda electrontransportinrealtimefromfirstprinciples |
| _version_ |
1807317965775831040 |