Source code for grogupy.physics.pair

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import copy
import warnings
from typing import Any, Iterator, Union

import numpy as np
import sisl
from numpy.typing import NDArray

from grogupy import __version__
from grogupy._core.utilities import arrays_lists_equal, arrays_None_equal

from .magnetic_entity import MagneticEntity
from .utilities import (
    calculate_exchange_tensor,
    calculate_isotropic_biquadratic_only,
    calculate_isotropic_only,
    fit_exchange_tensor,
    interaction_energy,
)


[docs] class Pair: """This class contains the data and the methods related to the pairs of magnetic entities. It sets up the instance based on the Hamiltonian of the DFT calculation, a pair of MagneticEntities and the supercell shift of the second MagneticEntities, given that the first one is not shifted. By default ``dh`` is ``None`` and we use the Hamiltonian from the magnetic entities. If the Hamiltonian from the two magnetic entities are different it raises an error. Parameters ---------- M1: MagneticEntity The first magnetic entity M2: MagneticEntity The second magnetic entity supercell_shift: Union[list, NDArray] The integer coordinates of the supercell shift Examples -------- The following examples show you how to create pairs in the **Fe3GeTe2** system. >>> fdf_path = "/Users/danielpozsar/Downloads/Fe3GeTe2/Fe3GeTe2.fdf" >>> Fe3 = MagneticEntity(fdf_path, atom=3, l=2) >>> Fe5 = MagneticEntity(fdf_path, atom=5, l=2) >>> pair_of_Fe = Pair(Fe3, Fe5, [0,0,0]) >>> print(pair_of_Fe) <grogupy.Pair tag1=3Fe(l:2), tag2=5Fe(l:2), Ruc=[0 0 0]> Methods ------- calculate_energies(weights) : Calculates the energies of the infinitesimal rotations. calculate_exchange_tensor() : Calculates the exchange tensor from the energies. fit_exchange_tensor(ref_xcf) : Fits the exchange tensor to the energies. copy() : Return a copy of this Pair Attributes ---------- M1: MagneticEntity The first magnetic entity M2: MagneticEntity The second magnetic entity supercell_shift: NDArray The supercell shift normed by the supercell vectors cell: NDArray The supercell vectors Gij: list Projected Greens function from M1 to M2 Gji: list Projected Greens function from M2 to M1 SBS1: int The SPIN BOX size of M1 SBS2: int The SPIN BOX size of M2 SBI1: NDArray The SPIN BOX indices of M1 SBI2: NDArray The SPIN BOX indices of M2 tags: list[str] The tags of the two magnetic entities supercell_shift_xyz: NDArray The supercell shift in real coordinates xyz: list[NDArray, NDArray] The coordinates of the magnetic entity (it can consist of many atoms) xyz_center: list[NDArray, NDArray] The center of coordinates for the magnetic entities distance: float The distance of the magnetic entities (it uses the center of coordinates for each magnetic entity) energies : Union[None, NDArray] The calculated energies for each direction self.J_iso: Union[float, None] Isotropic exchange, by default None self.J: Union[NDArray, None] Complete exchange tensor, by default None self.J_S: Union[NDArray, None] Symmetric exchange, by default None self.D: Union[NDArray, None] Dzyaloshinskii-Morilla vector, by default None Raises ------ Exception Different Hamiltonians from the magnetic entities """ number_of_pairs: int = 0
[docs] def __init__( self, M1: MagneticEntity, M2: MagneticEntity, supercell_shift: Union[list, NDArray] = np.array([0, 0, 0]), ) -> None: """This class contains the data and the methods related to the pairs of magnetic entities. It sets up the instance based on the Hamiltonian of the DFT calculation, a pair of MagneticEntities and the supercell shift of the second MagneticEntities, given that the first one is not shifted. By default ``dh`` is ``None`` and we use the Hamiltonian from the magnetic entities. If the Hamiltonian from the two magnetic entities are different it raises an error. Parameters ---------- M1: MagneticEntity The first magnetic entity M2: MagneticEntity The second magnetic entity supercell_shift: Union[list, NDArray] The integer coordinates of the supercell shift Examples -------- The following examples show you how to create pairs in the **Fe3GeTe2** system. >>> fdf_path = "/Users/danielpozsar/Downloads/Fe3GeTe2/Fe3GeTe2.fdf" >>> Fe3 = MagneticEntity(fdf_path, atom=3, l=2) >>> Fe5 = MagneticEntity(fdf_path, atom=5, l=2) >>> pair_of_Fe = Pair(Fe3, Fe5, [0,0,0]) >>> print(pair_of_Fe) <grogupy.Pair tag1=3Fe(l:2), tag2=5Fe(l:2), Ruc=[0 0 0]> """ if M1._dh is M2._dh: self._dh: sisl.physics.Hamiltonian = M1._dh elif arrays_lists_equal( M1._dh.Hk().toarray(), M2._dh.Hk().toarray() ) and arrays_lists_equal(M1._dh.Sk().toarray(), M2._dh.Sk().toarray()): self._dh: sisl.physics.Hamiltonian = M1._dh else: raise Exception("Different Hamiltonians from the magnetic entities!") self.M1: MagneticEntity = M1 self.M2: MagneticEntity = M2 self.supercell_shift: NDArray = np.array(supercell_shift) # initialize simulation parameters self._Gij: list[NDArray] = [] self._Gji: list[NDArray] = [] self.energies: Union[None, NDArray] = None self.J_iso: Union[None, float] = None self.J: Union[None, NDArray] = None self.J_S: Union[None, NDArray] = None self.D: Union[None, NDArray] = None # pre calculate hidden unuseed properties # they are here so they are dumped to the self.__dict__ upon saving self.__SBS1 = self.M1.SBS self.__SBS2 = self.M2.SBS self.__SBI1 = self.M1._spin_box_indices self.__SBI2 = self.M2._spin_box_indices self.__tags = [self.M1.tag, self.M2.tag] self.__cell = self._dh.cell self.__supercell_shift_xyz = self.supercell_shift @ self.cell self.__xyz = np.array( [self.M1._xyz, self.M2._xyz + self.supercell_shift_xyz], dtype=object ) self.__xyz_center = np.array( [self.M1.xyz_center, self.M2.xyz_center + self.supercell_shift_xyz] ) self.__distance = np.linalg.norm(self.xyz_center[0] - self.xyz_center[1]) self.__energies_meV = None self.__energies_mRy = None self.__J_meV = None self.__J_mRy = None self.__D_meV = None self.__D_mRy = None self.__J_S_meV = None self.__J_S_mRy = None self.__J_iso_meV = None self.__J_iso_mRy = None Pair.number_of_pairs += 1
def __getstate__(self): state = self.__dict__.copy() state["M1"] = state["M1"].__getstate__() state["M2"] = state["M2"].__getstate__() return state def __setstate__(self, state): M1 = object.__new__(MagneticEntity) M1.__setstate__(state["M1"]) state["M1"] = M1 M2 = object.__new__(MagneticEntity) M2.__setstate__(state["M2"]) state["M2"] = M2 self.__dict__ = state def __eq__(self, value): if isinstance(value, Pair): # if the IDs are identical, skip comaprison if id(self) == id(value): return True # if there are sisl Hamiltonians, then compare if self._dh is None and value._dh is None: pass else: if not arrays_lists_equal( self._dh.Hk().toarray(), value._dh.Hk().toarray() ): return False if not arrays_lists_equal( self._dh.Sk().toarray(), value._dh.Sk().toarray() ): return False if not self.M1 == value.M1: return False if not self.M2 == value.M2: return False if not arrays_lists_equal(self.supercell_shift, value.supercell_shift): return False if not arrays_lists_equal(self._Gij, value._Gij): return False if not arrays_lists_equal(self._Gji, value._Gji): return False if not arrays_None_equal(self.energies, value.energies): return False if not arrays_None_equal(self.J, value.J): return False if not arrays_None_equal(self.J_S, value.J_S): return False if not arrays_None_equal(self.D, value.D): return False # Checking J_iso separately # if both are None, then pass and no other check is perfomred because of elif if self.J_iso is None and value.J_iso is None: pass # if either one is None, but the other is not, then return false elif self.J_iso is not None and value.J_iso is None: return False elif self.J_iso is None and value.J_iso is not None: return False # If neither of them is None, compare them elif not np.isclose(self.J_iso, value.J_iso): return False return True else: return False def __repr__(self) -> str: """String representation of the instance.""" out = f"<grogupy.Pair tag1={self.tags[0]}, tag2={self.tags[1]}, Ruc={self.supercell_shift}>" return out @property def SBS1(self) -> int: """Spin box size of the first magnetic entity.""" self.__SBS1 = self.M1.SBS return self.__SBS1 @property def SBS2(self) -> int: """Spin box size of the second magnetic entity.""" self.__SBS2 = self.M2.SBS return self.__SBS2 @property def SBI1(self) -> NDArray: """Spin box indices of the first magnetic entity.""" self.__SBI1 = self.M1._spin_box_indices return self.__SBI1 @property def SBI2(self) -> NDArray: """Spin box indices of the second magnetic entity.""" self.__SBI2 = self.M2._spin_box_indices return self.__SBI2 @property def tags(self) -> list[str]: """Tags of the magnetic entities.""" self.__tags = [self.M1.tag, self.M2.tag] return self.__tags @property def cell(self): """Unit cell of the system.""" try: self.__cell = self._dh.cell except: warnings.warn( "Property could not be calculated. This is only acceptable for loaded Hamiltonian!" ) return self.__cell @property def supercell_shift_xyz(self) -> NDArray: """Supercell shift in Angstrom.""" self.__supercell_shift_xyz = self.supercell_shift @ self.cell return self.__supercell_shift_xyz @property def xyz(self) -> NDArray: """Coordinates of the magnetic entities.""" self.__xyz = np.array( [self.M1._xyz, self.M2._xyz + self.supercell_shift_xyz], dtype=object ) return self.__xyz @property def xyz_center(self) -> NDArray: """Center coordinates of the magnetic entities.""" self.__xyz_center = np.array( [self.M1.xyz_center, self.M2.xyz_center + self.supercell_shift_xyz] ) return self.__xyz_center @property def distance(self) -> float: """Distance of the magnetic entities.""" self.__distance = np.linalg.norm(self.xyz_center[0] - self.xyz_center[1]) return self.__distance @property def energies_meV(self) -> Union[None, NDArray]: """The energies, but in meV.""" if self.energies is None: self.__energies_meV = None else: self.__energies_meV = self.energies * sisl.unit_convert("eV", "meV") return self.__energies_meV @property def energies_mRy(self) -> Union[None, NDArray]: """The energies, but in mRy.""" if self.energies is None: self.__energies_mRy = None else: self.__energies_mRy = self.energies * sisl.unit_convert("eV", "mRy") return self.__energies_mRy @property def J_meV(self) -> Union[None, NDArray]: """The exchange tensor, but in meV.""" if self.J is None: self.__J_meV = None else: self.__J_meV = self.J * sisl.unit_convert("eV", "meV") return self.__J_meV @property def J_mRy(self) -> Union[None, NDArray]: """The exchange tensor, but in mRy.""" if self.J is None: self.__J_mRy = None else: self.__J_mRy = self.J * sisl.unit_convert("eV", "mRy") return self.__J_mRy @property def D_meV(self) -> Union[None, NDArray]: """The DM vector, but in meV.""" if self.D is None: self.__D_meV = None else: self.__D_meV = self.D * sisl.unit_convert("eV", "meV") return self.__D_meV @property def D_mRy(self) -> Union[None, NDArray]: """The DM vector, but in mRy.""" if self.D is None: self.__D_mRy = None else: self.__D_mRy = self.D * sisl.unit_convert("eV", "mRy") return self.__D_mRy @property def J_S_meV(self) -> Union[None, NDArray]: """The symmetric part of the exchange tensor, but in meV.""" if self.J_S is None: self.__J_S_meV = None else: self.__J_S_meV = self.J_S * sisl.unit_convert("eV", "meV") return self.__J_S_meV @property def J_S_mRy(self) -> Union[None, NDArray]: """The symmetric part of the exchange tensor, but in mRy.""" if self.J_S is None: self.__J_S_mRy = None else: self.__J_S_mRy = self.J_S * sisl.unit_convert("eV", "mRy") return self.__J_S_mRy @property def J_iso_meV(self) -> Union[None, NDArray]: """The isotropic exchange, but in meV.""" if self.J_iso is None: self.__J_iso_meV = None else: self.__J_iso_meV = self.J_iso * sisl.unit_convert("eV", "meV") return self.__J_iso_meV @property def J_iso_mRy(self) -> Union[None, NDArray]: """The isotropic exchange, but in mRy.""" if self.J_iso is None: self.__J_iso_mRy = None else: self.__J_iso_mRy = self.J_iso * sisl.unit_convert("eV", "mRy") return self.__J_iso_mRy def reset(self) -> None: """Resets the simulation results of the Pair. Does not reset the underlying Magnetic Entity instances. """ self._Gij: list[NDArray] = [] self._Gji: list[NDArray] = [] self.energies: Union[None, NDArray] = None self.J_iso: Union[None, float] = None self.J: Union[None, NDArray] = None self.J_S: Union[None, NDArray] = None self.D: Union[None, NDArray] = None def calculate_energies(self, weights: NDArray, append: bool = False) -> None: """Calculates the energies of the infinitesimal rotations. It uses the instance properties to calculate the energies and dumps the results to the `energies` property. Parameters ---------- weights: NDArray The weights of the energy contour integral append: bool, optional If it is True, then the energy of a single rotation is appended to the energies from the temporary storages, by default False """ if append: storage: list[float] = [] # iterate over the first order local perturbations in all possible orientations for the two sites # actually all possible orientations without the orientation for the off-diagonal anisotropy # that is why we only take the first two of each Vu1 for Vui in self.M1._Vu1_tmp[:2]: for Vuj in self.M2._Vu1_tmp[:2]: storage.append( interaction_energy( Vui, Vuj, self._Gij_tmp, self._Gji_tmp, weights ) ) if self.energies is None: self.energies = np.array(storage) else: self.energies = np.vstack((self.energies, np.array(storage))) else: energies: list[list[float]] = [] for i, (Gij, Gji) in enumerate(zip(self._Gij, self._Gji)): storage: list[float] = [] # iterate over the first order local perturbations in all possible orientations for the two sites # actually all possible orientations without the orientation for the off-diagonal anisotropy # that is why we only take the first two of each Vu1 for Vui in self.M1._Vu1[i][:2]: for Vuj in self.M2._Vu1[i][:2]: storage.append(interaction_energy(Vui, Vuj, Gij, Gji, weights)) # fill up the pairs dictionary with the energies energies.append(storage) self.energies: NDArray = np.array(energies) # call these so they are updated self.energies_meV self.energies_mRy def calculate_exchange_tensor(self) -> None: """Calculates the exchange tensor from the energies. It uses the instance properties to calculate the exchange tensor and its different representations and dumps them to the `J`, `J_iso`, `J_S` and `D` properties. """ J_iso, J_S, D, J = calculate_exchange_tensor(self.energies) self.J: Union[None, NDArray] = J self.J_S: Union[None, NDArray] = J_S self.J_iso: Union[None, float] = J_iso self.D: Union[None, NDArray] = D # call these so they are updated self.J_meV self.J_mRy self.J_S_meV self.J_S_mRy self.J_iso_meV self.J_iso_mRy self.D_meV self.D_mRy def fit_exchange_tensor(self, ref_xcf: list[dict]) -> None: """Fits the exchange tensor to the energies. It uses a fitting method to calculate the exchange tensor from the reference directions and its different representations and dumps them to the `J`, `J_iso`, `J_S` and `D` properties. Parameters ---------- ref_xcf: list[dict] The reference directions containing the orientation and perpendicular directions """ J_iso, J_S, D, J = fit_exchange_tensor(self.energies, ref_xcf) self.J: Union[None, NDArray] = J self.J_S: Union[None, NDArray] = J_S self.J_iso: Union[None, float] = J_iso self.D: Union[None, NDArray] = D # call these so they are updated self.J_meV self.J_mRy self.J_S_meV self.J_S_mRy self.J_iso_meV self.J_iso_mRy self.D_meV self.D_mRy def calculate_isotropic_only(self) -> None: """Calculates the isotropic exchange only. It uses the instance properties to calculate the isotropic exchange. It resets the other properties, but they can be recalculated from the energies. """ J_iso = calculate_isotropic_only(self.energies) self.J: Union[None, NDArray] = None self.J_S: Union[None, NDArray] = None self.J_iso: Union[None, float] = J_iso self.D: Union[None, NDArray] = None # call these so they are updated self.J_meV self.J_mRy self.J_S_meV self.J_S_mRy self.J_iso_meV self.J_iso_mRy self.D_meV self.D_mRy def calculate_isotropic_biquadratic_only(self) -> None: """Calculates the isotropic and biquadratic isotropic exchange. It uses the instance properties to calculate the isotropic and biquadratic isotropic exchange. It resets the other properties, but they can be recalculated from the energies. """ J_iso = calculate_isotropic_biquadratic_only(self.energies) self.J: Union[None, NDArray] = None self.J_S: Union[None, NDArray] = None self.J_iso: Union[None, float] = J_iso self.D: Union[None, NDArray] = None # call these so they are updated self.J_meV self.J_mRy self.J_S_meV self.J_S_mRy self.J_iso_meV self.J_iso_mRy self.D_meV self.D_mRy def copy(self): """Returns the deepcopy of the instance. Returns ------- Pair The copied instance. """ return copy.deepcopy(self)
[docs] class PairList: """List of Pairs. It supports easier attribute access across the Pairs in the list. """
[docs] def __init__(self, pairs: Union[None, list[Pair], NDArray] = None): if pairs is None: self.__pairs = [] elif isinstance(pairs, PairList): self.__pairs = pairs.__pairs elif isinstance(pairs, list) or isinstance(pairs, np.ndarray): self.__pairs = list(pairs) else: raise Exception(f"Bad input type: {type(pairs)}!")
def __len__(self): return len(self.__pairs) def __iter__(self) -> Iterator[Pair]: return iter(self.__pairs) def __add__(self, other): if isinstance(other, PairList): other = other.__pairs elif isinstance(other, list): pass elif isinstance(other, np.ndarray): other = other.tolist() else: raise Exception( "Only list, np.ndparray and PairList can be added to PairList" ) return PairList(self.__pairs + other) def __getstate__(self) -> dict: state = self.__dict__.copy() out = [] for p in state["_PairList__pairs"]: out.append(p.__getstate__()) state["_PairList__pairs"] = out return state def __setstate__(self, state) -> None: out = [] for p in state["_PairList__pairs"]: temp = object.__new__(Pair) temp.__setstate__(p) out.append(temp) state["_PairList__pairs"] = out self.__dict__ = state def __getattr__(self, name) -> NDArray: try: return np.array([p.__getattribute__(name) for p in self.__pairs]) except: return np.array( [p.__getattribute__(name) for p in self.__pairs], dtype=object ) def __getitem__(self, item: int) -> Pair: return self.__pairs[item] def __repr__(self) -> str: """String representation of the instance.""" out = f"<grogupy.PairList length={len(self.__pairs)}>" return out def __str__(self) -> str: """String of the instance.""" out = "[" + "\n".join([p.__repr__() for p in self.__pairs]) + "]" return out def append(self, item): """Appends to the pair list.""" if isinstance(item, Pair): self.__pairs.append(item) else: raise Exception("This class is reserved for Pair instances only!") def tolist(self) -> list[Pair]: """Returns a list from the underlying data. Returns ------- list The pairs in a list format. """ return self.__pairs def toarray(self) -> NDArray: """Returns a numpy array from the underlying data. Returns ------- NDArray The pairs in a numpy array. """ return np.array(self.__pairs, dtype=object)
if __name__ == "__main__": pass