nrgljubljana_interface.solver.Solver

class nrgljubljana_interface.solver.Solver(*args, **params_kw)

Bases: SolverCore

NRGLjubljana impurity solver.

Thin Python wrapper over the compiled SolverCore. Construct it with the model, symmetry type and frequency mesh, assign the hybridization function S.Delta_w['imp'] << ..., then call solve() and read the results (S.A_w, S.G_w, S.Sigma_w, …).

The __init__(), solve() and set_nrg_params() methods each accept either keyword arguments (which are used to build the corresponding parameter object) or a single parameter object positionally, so a stored S.constr_params / S.last_solve_params / S.nrg_params can be passed straight back in.

Parameters:

argsConstrParamsT, optional

A construction-parameter object (e.g. a stored constr_params) passed positionally, instead of the keyword arguments below.

modelstr, optional

Impurity model to solve (selects a template directory), e.g. 'SIAM'. Default 'SIAM'.

symtypestr, optional

NRGLjubljana symmetry code, e.g. 'QS', 'QSZ', 'ISO'. Default 'QS'.

mesh_maxfloat, optional

Maximum frequency of the logarithmic mesh. Default 10.

mesh_minfloat, optional

Minimum frequency of the logarithmic mesh. Default 1e-4.

mesh_ratiofloat, optional

Common ratio of the geometric (logarithmic) frequency mesh. Default 1.05.

Attributes

A_w	The spectral function \(A(\omega)\).
B_l_w	The spectral function \(B_l(\omega)\) of the auxiliary correlator \(F_l(\omega)\).
B_r_w	The spectral function \(B_r(\omega)\) of the auxiliary correlator \(F_r(\omega)\).
C_w	The spectral function \(C(\omega)\) of the auxiliary correlator \(I(\omega)\).
Delta_struct	The hybridization function structure object.
Delta_w	The hybridization function on the real-frequency axis.
F_l_w	The auxiliary Green's function \(F_l(\omega) = \Sigma(\omega)\, G(\omega)\).
F_r_w	The auxiliary Green's function \(F_r(\omega) = G(\omega)\, \Sigma(\omega)\).
G_w	The retarded Green's function \(G(\omega)\).
I_w	The auxiliary Green's function \(I(\omega)\).
SigmaHartree_w	Constant Hartree shift to the self-energy, stored as a Green's function.
Sigma_w	The retarded self-energy \(\Sigma(\omega)\) (computed from \(F_l\), \(F_r\), \(G\) and \(I\)).
chi_NN_w	Charge susceptibility \(\chi_{NN}(\omega)\).
chi_SS_w	Spin susceptibility \(\chi_{SS}(\omega)\).
chi_struct	The susceptibility structure object.
constr_params	Parameters used for the solver construction.
expv	Expectation values of local impurity operators.
gf_struct	The Green's function structure object.
keep_temp_dir	Keep the temporary directories after the calculation.
last_solve_params	Parameters used for the most recent solve process.
log_mesh	Logarithmic real-frequency mesh.
nrg_params	Low-level NRG parameters.
tdfdm	Thermodynamic variables (FDM algorithm).
verbose	If true, detailed output from NRGLjubljana and its tools is sent to stdout.

Methods

be_quiet	Suppress verbose output from the NRG solver.
check_model_params	Check that all required model parameters have been defined.
create_tempdir	Create a temporary working directory for a series of NRG runs.
generate_param_file	Produce the param file for a given value of the twist parameter \(z\).
instantiate	Prepare the input files for an individual NRG calculation.
read_structure	Read the block structure of Green's function objects from a file.
readexpv	Read expectation values from the NRG output files.
readtdfdm	Read thermodynamic variables (FDM algorithm) from the NRG output files.
set_nrg_params(*args, **params_kw)	Set the advanced (low-level) NRG parameters.
set_params	Establish good defaults for the low-level NRG parameters.
set_verbosity	Set the verbosity (see also be_quiet()).
solve(*args, **params_kw)	Solve the impurity problem.
solve_one	Perform an individual NRG calculation.
write_gamma	Write \(\Gamma = -\mathrm{Im}\,\Delta(\omega)\) to a file.

Notes

See ConstrParamsT for the full list of construction parameters.