calculatePhononRetardedGreenFunction¶
- calculatePhononRetardedGreenFunction(device_configuration, dynamical_matrix=None, energy=PhysicalQuantity(0.0, eV), kpoint=None, eta=PhysicalQuantity(1e-06, Hartree), self_energy_calculator=None)¶
Calculate the Phonon Retarded Green’s Function.
- Parameters:
device_configuration (
DeviceConfiguration
) – The configuration to use for the calculation.dynamical_matrix (
DynamicalMatrix
) – The dynamical matrix to use in the calculation.energy (PhysicalQuantity of type energy) – Absolute energy for the calculation Default:
0.0 * eV
kpoint (tuple of floats) – The kpoint as three floats representing fractional reciprocal space coordinates. Default: The Gamma point
(0.0, 0.0, 0.0)
eta (PhysicalQuantity of type energy) – Complex energy for electrode transform matrices, imaginary part. Default:
1.0e-6 * Hartree
self_energy_calculator (
RecursionSelfEnergy
|DirectSelfEnergy
|KrylovSelfEnergy
|SparseRecursionSelfEnergy
) – The self energy evaluation strategy to use. Default: A defaultRecursionSelfEnergy
instance.
- Returns:
The Phonons Green’s Function as an array
- Return type:
PhysicalQuantity of type energy squared
Usage Examples¶
Evaluate on a DeviceConfiguration:
phonon_green_function = calculatePhononRetardedGreenFunction(device_configuration)
Notes¶
The calculator assigned to the device must be density matrix-based for this function to perform successfully.