mirror of
https://github.com/triqs/dft_tools
synced 2024-11-01 03:33:50 +01:00
46 lines
1.9 KiB
Python
46 lines
1.9 KiB
Python
|
from pytriqs.gf.local import *
|
||
|
|
from pytriqs.operators import *
|
||
|
|
from pytriqs.archive import *
|
||
|
|
import pytriqs.utility.mpi as mpi
|
||
|
|
|
||
|
|
# Set up a few parameters
|
||
|
|
U = 2.5
|
||
|
|
half_bandwidth = 1.0
|
||
|
|
chemical_potential = U/2.0
|
||
|
|
beta = 100
|
||
|
|
n_loops = 5
|
||
|
|
|
||
|
|
# Construct the CTQMC solver
|
||
|
|
from pytriqs.applications.impurity_solvers.cthyb_matrix import Solver
|
||
|
|
S = Solver(beta = beta, gf_struct = [ ('up',[1]), ('down',[1]) ])
|
||
|
|
|
||
|
|
# Initalize the Green's function to a semi circular
|
||
|
|
S.G <<= SemiCircular(half_bandwidth)
|
||
|
|
|
||
|
|
# Now do the DMFT loop
|
||
|
|
for IterationNumber in range(n_loops):
|
||
|
|
|
||
|
|
# Compute S.G0 with the self-consistency condition while imposing paramagnetism
|
||
|
|
g = 0.5 * ( S.G['up'] + S.G['down'] )
|
||
|
|
for name, g0block in S.G0:
|
||
|
|
g0block <<= inverse( iOmega_n + chemical_potential - (half_bandwidth/2.0)**2 * g )
|
||
|
|
|
||
|
|
# Run the solver
|
||
|
|
S.solve(H_local = U * N('up',1) * N('down',1), # Local Hamiltonian
|
||
|
|
quantum_numbers = { 'Nup' : N('up',1), 'Ndown' : N('down',1) }, # Quantum Numbers (operators commuting with H_Local)
|
||
|
|
n_cycles = 5000, # Number of QMC cycles
|
||
|
|
length_cycle = 200, # Length of a cycle
|
||
|
|
n_warmup_cycles = 1000, # How many warmup cycles
|
||
|
|
n_legendre = 30, # Use 30 Legendre coefficients to represent G(tau)
|
||
|
|
random_name = "mt19937", # Use the Mersenne Twister 19937 random generator
|
||
|
|
use_segment_picture = True) # Here we can use the segment picture
|
||
|
|
|
||
|
|
# Some intermediate saves
|
||
|
|
if mpi.is_master_node():
|
||
|
|
R = HDFArchive("single_site_bethe.h5")
|
||
|
|
R["G-%s"%IterationNumber] = S.G
|
||
|
|
del R
|
||
|
|
|
||
|
|
# Here we would usually write some convergence test
|
||
|
|
# if Converged : break
|