# -*- coding: utf-8 -*- # ------------------------------------------------------------- # Two-probe Configuration # ------------------------------------------------------------- # ------------------------------------------------------------- # Left Electrode # ------------------------------------------------------------- # Set up lattice vector_a = [10.0, 0.0, 0.0]*Angstrom vector_b = [0.0, 17.1043, 0.0]*Angstrom vector_c = [0.0, 0.0, 7.38300513133]*Angstrom left_electrode_lattice = UnitCell(vector_a, vector_b, vector_c) # Define elements left_electrode_elements = [Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon] # Define coordinates left_electrode_coordinates = [[ 5. , 3.91000051, 0.61525043], [ 5. , 5. , 0.61525043], [ 5. , 7.84172 , 0.61525043], [ 5. , 9.26258 , 0.61525043], [ 5. , 12.1043 , 0.61525043], [ 5. , 13.19429949, 0.61525043], [ 5. , 5.71043 , 1.84575128], [ 5. , 7.13129 , 1.84575128], [ 5. , 9.97301 , 1.84575128], [ 5. , 11.39387 , 1.84575128], [ 5. , 3.91000051, 3.07625214], [ 5. , 5. , 3.07625214], [ 5. , 7.84172 , 3.07625214], [ 5. , 9.26258 , 3.07625214], [ 5. , 12.1043 , 3.07625214], [ 5. , 13.19429949, 3.07625214], [ 5. , 5.71043 , 4.30675299], [ 5. , 7.13129 , 4.30675299], [ 5. , 9.97301 , 4.30675299], [ 5. , 11.39387 , 4.30675299], [ 5. , 3.91000051, 5.53725385], [ 5. , 5. , 5.53725385], [ 5. , 7.84172 , 5.53725385], [ 5. , 9.26258 , 5.53725385], [ 5. , 12.1043 , 5.53725385], [ 5. , 13.19429949, 5.53725385], [ 5. , 5.71043 , 6.7677547 ], [ 5. , 7.13129 , 6.7677547 ], [ 5. , 9.97301 , 6.7677547 ], [ 5. , 11.39387 , 6.7677547 ]]*Angstrom # Set up configuration left_electrode = BulkConfiguration( bravais_lattice=left_electrode_lattice, elements=left_electrode_elements, cartesian_coordinates=left_electrode_coordinates ) # ------------------------------------------------------------- # Right Electrode # ------------------------------------------------------------- # Set up lattice vector_a = [10.0, 0.0, 0.0]*Angstrom vector_b = [0.0, 17.1043, 0.0]*Angstrom vector_c = [0.0, 0.0, 7.38300513133]*Angstrom right_electrode_lattice = UnitCell(vector_a, vector_b, vector_c) # Define elements right_electrode_elements = [Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon] # Define coordinates right_electrode_coordinates = [[ 5. , 3.91000051, 0.61525043], [ 5. , 5. , 0.61525043], [ 5. , 7.84172 , 0.61525043], [ 5. , 9.26258 , 0.61525043], [ 5. , 12.1043 , 0.61525043], [ 5. , 13.19429949, 0.61525043], [ 5. , 5.71043 , 1.84575128], [ 5. , 7.13129 , 1.84575128], [ 5. , 9.97301 , 1.84575128], [ 5. , 11.39387 , 1.84575128], [ 5. , 3.91000051, 3.07625214], [ 5. , 5. , 3.07625214], [ 5. , 7.84172 , 3.07625214], [ 5. , 9.26258 , 3.07625214], [ 5. , 12.1043 , 3.07625214], [ 5. , 13.19429949, 3.07625214], [ 5. , 5.71043 , 4.30675299], [ 5. , 7.13129 , 4.30675299], [ 5. , 9.97301 , 4.30675299], [ 5. , 11.39387 , 4.30675299], [ 5. , 3.91000051, 5.53725385], [ 5. , 5. , 5.53725385], [ 5. , 7.84172 , 5.53725385], [ 5. , 9.26258 , 5.53725385], [ 5. , 12.1043 , 5.53725385], [ 5. , 13.19429949, 5.53725385], [ 5. , 5.71043 , 6.7677547 ], [ 5. , 7.13129 , 6.7677547 ], [ 5. , 9.97301 , 6.7677547 ], [ 5. , 11.39387 , 6.7677547 ]]*Angstrom # Set up configuration right_electrode = BulkConfiguration( bravais_lattice=right_electrode_lattice, elements=right_electrode_elements, cartesian_coordinates=right_electrode_coordinates ) # ------------------------------------------------------------- # Central Region # ------------------------------------------------------------- # Set up lattice vector_a = [10.0, 0.0, 0.0]*Angstrom vector_b = [0.0, 17.1043, 0.0]*Angstrom vector_c = [0.0, 0.0, 29.5320205253]*Angstrom central_region_lattice = UnitCell(vector_a, vector_b, vector_c) # Define elements central_region_elements = [Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon, Hydrogen, Carbon, Carbon, Carbon, Carbon] # Define coordinates central_region_coordinates = [[ 5. , 3.91000051, 0.61525043], [ 5. , 5. , 0.61525043], [ 5. , 7.84172 , 0.61525043], [ 5. , 9.26258 , 0.61525043], [ 5. , 12.1043 , 0.61525043], [ 5. , 13.19429949, 0.61525043], [ 5. , 5.71043 , 1.84575128], [ 5. , 7.13129 , 1.84575128], [ 5. , 9.97301 , 1.84575128], [ 5. , 11.39387 , 1.84575128], [ 5. , 3.91000051, 3.07625214], [ 5. , 5. , 3.07625214], [ 5. , 7.84172 , 3.07625214], [ 5. , 9.26258 , 3.07625214], [ 5. , 12.1043 , 3.07625214], [ 5. , 13.19429949, 3.07625214], [ 5. , 5.71043 , 4.30675299], [ 5. , 7.13129 , 4.30675299], [ 5. , 9.97301 , 4.30675299], [ 5. , 11.39387 , 4.30675299], [ 5. , 3.91000051, 5.53725385], [ 5. , 5. , 5.53725385], [ 5. , 7.84172 , 5.53725385], [ 5. , 9.26258 , 5.53725385], [ 5. , 12.1043 , 5.53725385], [ 5. , 13.19429949, 5.53725385], [ 5. , 5.71043 , 6.7677547 ], [ 5. , 7.13129 , 6.7677547 ], [ 5. , 9.97301 , 6.7677547 ], [ 5. , 11.39387 , 6.7677547 ], [ 5. , 3.93873624, 7.9900128 ], [ 5. , 5.02983086, 8.0006382 ], [ 5. , 7.83307725, 7.98417408], [ 5. , 9.24198158, 7.94137127], [ 5. , 12.11763076, 7.93386665], [ 5. , 13.2077171 , 7.9291557 ], [ 5. , 5.69624251, 9.23480042], [ 5. , 7.11343444, 9.20234198], [ 5. , 9.98854354, 9.10862823], [ 5. , 11.41351558, 9.11677813], [ 5. , 3.99457392, 10.54646416], [ 5. , 5.08525218, 10.49866335], [ 5. , 7.85341583, 10.40268127], [ 5. , 9.25173286, 10.28273433], [ 5. , 12.14711386, 10.28692506], [ 5. , 13.23525704, 10.26768464], [ 5. , 5.80432767, 11.70853725], [ 5. , 7.22789244, 11.68042132], [ 5. , 10.00686704, 11.41409073], [ 5. , 11.43919409, 11.44876684], [ 5. , 4.10135285, 13.01248231], [ 5. , 5.1911716 , 12.96030342], [ 5. , 8.01845569, 12.88858377], [ 5. , 9.42616869, 12.71982192], [ 5. , 11.81576577, 12.78126574], [ 5. , 12.82202432, 13.19251511], [ 5. , 10.61645882, 13.50849837], [ 5. , 5.91250774, 14.16170138], [ 5. , 7.35153719, 14.16542691], [ 5. , 10.61534033, 14.83542496], [ 5. , 4.10150001, 15.30937876], [ 5. , 5.19106012, 15.36203785], [ 5. , 8.01780494, 15.44400533], [ 5. , 9.42449408, 15.62193714], [ 5. , 11.81316377, 15.56519189], [ 5. , 12.81666936, 15.14697787], [ 5. , 5.80282331, 16.61379531], [ 5. , 7.22545814, 16.64998715], [ 5. , 10.00205002, 16.92973559], [ 5. , 11.43491855, 16.89754786], [ 5. , 3.98896429, 17.76618413], [ 5. , 5.07933548, 17.81851703], [ 5. , 7.84739469, 17.93057531], [ 5. , 9.24476366, 18.06047001], [ 5. , 12.13974473, 18.06181835], [ 5. , 13.22803196, 18.08278849], [ 5. , 5.68671339, 19.08261466], [ 5. , 7.10413659, 19.12828784], [ 5. , 9.9805564 , 19.23621365], [ 5. , 11.40378261, 19.23105071], [ 5. , 3.91323329, 20.30430217], [ 5. , 5.00460547, 20.3057868 ], [ 5. , 7.82221797, 20.34986905], [ 5. , 9.24029594, 20.40905578], [ 5. , 12.10546319, 20.41439833], [ 5. , 13.19499461, 20.41701068], [ 5. , 5.67579273, 21.53870293], [ 5. , 7.09855712, 21.56040289], [ 5. , 9.98453125, 21.58482474], [ 5. , 11.3936403 , 21.58978815], [ 5. , 3.91000051, 22.76426582], [ 5. , 5. , 22.76426582], [ 5. , 7.84172 , 22.76426582], [ 5. , 9.26258 , 22.76426582], [ 5. , 12.1043 , 22.76426582], [ 5. , 13.19429949, 22.76426582], [ 5. , 5.71043 , 23.99476668], [ 5. , 7.13129 , 23.99476668], [ 5. , 9.97301 , 23.99476668], [ 5. , 11.39387 , 23.99476668], [ 5. , 3.91000051, 25.22526753], [ 5. , 5. , 25.22526753], [ 5. , 7.84172 , 25.22526753], [ 5. , 9.26258 , 25.22526753], [ 5. , 12.1043 , 25.22526753], [ 5. , 13.19429949, 25.22526753], [ 5. , 5.71043 , 26.45576839], [ 5. , 7.13129 , 26.45576839], [ 5. , 9.97301 , 26.45576839], [ 5. , 11.39387 , 26.45576839], [ 5. , 3.91000051, 27.68626924], [ 5. , 5. , 27.68626924], [ 5. , 7.84172 , 27.68626924], [ 5. , 9.26258 , 27.68626924], [ 5. , 12.1043 , 27.68626924], [ 5. , 13.19429949, 27.68626924], [ 5. , 5.71043 , 28.9167701 ], [ 5. , 7.13129 , 28.9167701 ], [ 5. , 9.97301 , 28.9167701 ], [ 5. , 11.39387 , 28.9167701 ]]*Angstrom # Set up configuration central_region = BulkConfiguration( bravais_lattice=central_region_lattice, elements=central_region_elements, cartesian_coordinates=central_region_coordinates ) device_configuration = DeviceConfiguration( central_region, [left_electrode, right_electrode], equivalent_electrode_lengths=[7.38300513133, 7.38300513133]*Angstrom, ) # ------------------------------------------------------------- # Calculator # ------------------------------------------------------------- #---------------------------------------- # Hamiltonian Parametrization #---------------------------------------- basis_set = [ HoffmannHuckelParameters.Hydrogen_Basis, CerdaHuckelParameters.Carbon_graphite_Basis, ] hamiltonian_parametrization = HuckelHamiltonianParametrization( basis_set=basis_set) #---------------------------------------- # Numerical Accuracy Settings #---------------------------------------- left_electrode_k_point_sampling = MonkhorstPackGrid( nc=128, k_point_shift=[0.0, 0.0, 0.0], ) left_electrode_numerical_accuracy_parameters = NumericalAccuracyParameters( k_point_sampling=left_electrode_k_point_sampling, density_mesh_cutoff=20.0*Hartree, ) right_electrode_k_point_sampling = MonkhorstPackGrid( nc=128, k_point_shift=[0.0, 0.0, 0.0], ) right_electrode_numerical_accuracy_parameters = NumericalAccuracyParameters( k_point_sampling=right_electrode_k_point_sampling, density_mesh_cutoff=20.0*Hartree, ) device_k_point_sampling = MonkhorstPackGrid( nc=128, k_point_shift=[0.0, 0.0, 0.0], ) device_numerical_accuracy_parameters = NumericalAccuracyParameters( k_point_sampling=device_k_point_sampling, density_mesh_cutoff=20.0*Hartree, ) #---------------------------------------- # Iteration Control Settings #---------------------------------------- left_electrode_iteration_control_parameters = IterationControlParameters( tolerance=4e-05, ) right_electrode_iteration_control_parameters = IterationControlParameters( tolerance=4e-05, ) device_iteration_control_parameters = IterationControlParameters( tolerance=4e-05, ) #---------------------------------------- # Poisson Solver Settings #---------------------------------------- left_electrode_poisson_solver = FastFourier2DSolver( boundary_conditions=[[PeriodicBoundaryCondition(),PeriodicBoundaryCondition()], [PeriodicBoundaryCondition(),PeriodicBoundaryCondition()], [PeriodicBoundaryCondition(),PeriodicBoundaryCondition()]] ) right_electrode_poisson_solver = FastFourier2DSolver( boundary_conditions=[[PeriodicBoundaryCondition(),PeriodicBoundaryCondition()], [PeriodicBoundaryCondition(),PeriodicBoundaryCondition()], [PeriodicBoundaryCondition(),PeriodicBoundaryCondition()]] ) #---------------------------------------- # Electrode Calculators #---------------------------------------- left_electrode_calculator = SemiEmpiricalCalculator( hamiltonian_parametrization=hamiltonian_parametrization, numerical_accuracy_parameters=left_electrode_numerical_accuracy_parameters, iteration_control_parameters=left_electrode_iteration_control_parameters, poisson_solver=left_electrode_poisson_solver, ) right_electrode_calculator = SemiEmpiricalCalculator( hamiltonian_parametrization=hamiltonian_parametrization, numerical_accuracy_parameters=right_electrode_numerical_accuracy_parameters, iteration_control_parameters=right_electrode_iteration_control_parameters, poisson_solver=right_electrode_poisson_solver, ) #---------------------------------------- # Device Calculator #---------------------------------------- calculator = DeviceSemiEmpiricalCalculator( hamiltonian_parametrization=hamiltonian_parametrization, numerical_accuracy_parameters=device_numerical_accuracy_parameters, iteration_control_parameters=device_iteration_control_parameters, electrode_calculators= [left_electrode_calculator, right_electrode_calculator], ) device_configuration.setCalculator(calculator) nlprint(device_configuration) device_configuration.update() nlsave('nanoribbon.hdf5', device_configuration) # ------------------------------------------------------------- # IV Characteristics # ------------------------------------------------------------- # Kpoint sampling kpoint_grid = MonkhorstPackGrid() # Gate-source voltages gate_source_voltages = numpy.linspace(0, 0, 1)*Volt # Drain-source voltages drain_source_voltages = numpy.linspace(0, 1, 11)*Volt # File name. filename = u'nanoribbon.hdf5' iv_characteristics = IVCharacteristics( configuration=device_configuration, filename=filename, object_id='ivcharacteristics', gate_regions=[], gate_source_voltages=gate_source_voltages, drain_source_voltages=drain_source_voltages, energies=None, kpoints=kpoint_grid, self_energy_calculator=RecursionSelfEnergy(), energy_zero_parameter=AverageFermiLevel, infinitesimal=1e-06*eV, log_filename_prefix='ivcharacteristics_', number_of_processes_per_task=None, ) iv_characteristics.update() # ------------------------------------------------------------- # TransmissionEigenstate analysis for quantum numbers [0,1,2] # ------------------------------------------------------------- for i in [0,1,2]: iv_characteristics.addAnalysis( 0.0 * Volt, 0.0 * Volt, TransmissionEigenstate, {'quantum_number': i} ) # Update IV characteristics again. iv_characteristics.update()