def get_xas(eval_i,
eval_n,
dipole_ops,
om_mesh=np.linspace(-10, 20, 1000),
om_offset=857.40,
thin=115 / 180.0 * np.pi,
phi=0.0,
gamma_c=0.2,
T=30.):
'''
Calculate XAS spectrum.
Parameters
----------
eval_i: array
Eigenvalues of initial state Hamiltonian
eval_n: array
Eigenvalues of intermediate state Hamiltonian
dipole_op: array
Dipole operator from 2p to 3d state
om_mesh: array
Incident energies to calculate the spectrum.
In eV without the offset.
om_offset: float
Offset between theoretical and experimental energy axes
thin: float
Incident x-ray angle in radians w.r.t. plane perpendicular to the
c-axis
phi: float
Azimutal x-ray angle in radians
gamma_c: float
core-hole life-time broadening
T: float
Temperature in Kelvin
Returns
-------
om_mesh: array
Incident energies to calculate the spectrum.
In eV without the offset.
om_offset: float
Offset between theoretical and experimental energy axes
xas: array
X-ray absorption intensity. Shape (len(om_mesh), 5)
Where the last axis denotes the polarization
Linear pi
Linear sigma
Circular left
Circular right
Isotropic
'''
poltype = [('linear', 0.0), ('linear', np.pi / 2.0), ('left', 0.0),
('right', 0.0), ('isotropic', 0.0)]
xas = edrixs.xas_1v1c_py(eval_i,
eval_n,
dipole_ops,
om_mesh,
gamma_c=gamma_c,
thin=thin,
phi=phi,
pol_type=poltype,
gs_list=[0, 1, 2],
temperature=T)
return om_mesh, om_offset, xas
# Run ED
eval_i, eval_n, trans_op = edrixs.ed_1v1c_py(('d', 'p'),
shell_level=(0.0, -off),
v_soc=(zeta_d_i, zeta_d_n),
c_soc=zeta_p_n,
v_noccu=noccu,
slater=slater,
v_cfmat=cf)
# Run XAS
xas = edrixs.xas_1v1c_py(eval_i,
eval_n,
trans_op,
ominc_xas,
gamma_c=gamma_c,
thin=thin,
phi=phi,
pol_type=poltype_xas,
gs_list=[0, 1, 2],
temperature=300)
# Run RIXS at L3 edge
rixs_L3 = edrixs.rixs_1v1c_py(eval_i,
eval_n,
trans_op,
ominc_rixs_L3,
eloss,
gamma_c=gamma_c,
gamma_f=gamma_f,
thin=thin,
thout=thout,
# broadening is domainted by the inverse core hole lifetime :code:`gamma_c`,
# which is the Lorentzian half width at half maximum.
ominc = np.linspace(11200, 11230, 50)
temperature = 300 # in K
prob = edrixs.boltz_dist(eval_i, temperature)
gs_list = [n for n, prob in enumerate(prob) if prob>1e-6]
gs_list = [n for n in range(6)]
thin = 30*np.pi/180
phi = 0
pol_type = [('linear', 0)]
xas = edrixs.xas_1v1c_py(
eval_i, eval_n, trans_op, ominc, gamma_c=info['gamma_c'],
thin=thin, phi=phi, pol_type=pol_type,
gs_list=gs_list)
################################################################################
# Compute RIXS
# ------------------------------------------------------------------------------
# Calculating RIXS is overall similar to XAS, but with a few additional
# considerations. The spectral width in the energy loss axis of RIXS it
# not set by the core hole lifetime, but by either the final state lifetime
# or the experimental resolution and is parameterized by :code:`gamma_f`
# -- the Lorentzian half width at half maximum.
#
# The angle and polarization of the emitted beam must also be specified.
# If, as is common in experiments, the emitted polarization is not resolved
# one needs to add both emitted polarization channels, which is what we will