def get_transop(loc, pos):
    # get dipole transition operator in local axis
    dop = edrixs.get_trans_oper('t2gp32')
    dop_g = np.zeros((2, 3, 6, 4), dtype=np.complex)
    # transform to golobal axis
    for i in range(2):
        for j in range(3):
            for k in range(3):
                dop_g[i, j] += loc[i, j, k] * dop[k]

    # RIXS settings
    thin, thout, phi = 30 / 180.0 * np.pi, 60 / 180.0 * np.pi, 0.0
    ein, eout = 11215.0, 11215.0  # eV
    # Wavevector
    kin, kout = edrixs.get_wavevector_rixs(thin, thout, phi, ein, eout)
    # polarization pi-pi and pi-sigma
    for key, alpha, beta in [('pp', 0, 0), ('ps', 0, np.pi / 2.0)]:
        ei, ef = edrixs.dipole_polvec_rixs(thin, thout, phi, alpha, beta)
        T_i = np.zeros((2, 6, 4), dtype=np.complex)
        T_f = np.zeros((2, 4, 6), dtype=np.complex)
        for i in range(2):
            for j in range(3):
                T_i[i] += dop_g[i, j] * ei[j]
                T_f[i] += np.conj(np.transpose(dop_g[i, j] * ef[j]))
            # multiply phase factor
            T_i[i] = T_i[i] * np.exp(+1j * np.dot(pos[i], kin))
            T_f[i] = T_f[i] * np.exp(-1j * np.dot(pos[i], kout))

        transop_rixs_i = np.zeros((20, 20), dtype=np.complex)
        transop_rixs_f = np.zeros((20, 20), dtype=np.complex)
        for i in range(2):
            off1, off2 = i * 6, 12 + i * 4
            transop_rixs_i[off1:off1 + 6, off2:off2 + 4] = T_i[i]
            transop_rixs_f[off2:off2 + 4, off1:off1 + 6] = T_f[i]
        # write to file
        edrixs.write_emat(transop_rixs_i, "rixs_" + key + "/transop_rixs_i.in")
        edrixs.write_emat(transop_rixs_f, "rixs_" + key + "/transop_rixs_f.in")

    # For XAS, use isotropic polarization
    ei = np.array([1, 1, 1]) / np.sqrt(3.0)
    T_i = np.zeros((2, 6, 4), dtype=np.complex)
    for i in range(2):
        for j in range(3):
            T_i[i] += dop_g[i, j] * ei[j]

    transop_xas = np.zeros((20, 20), dtype=np.complex128)
    for i in range(2):
        off1, off2 = i * 6, 12 + i * 4
        transop_xas[off1:off1 + 6, off2:off2 + 4] = T_i[i]
    edrixs.write_emat(transop_xas, "xas/transop_xas.in")
示例#2
0
def get_transop(loc, pos):
    dop = edrixs.get_trans_oper('t2gp')
    dop_g = np.zeros((2, 3, 6, 6), dtype=np.complex)
    for i in range(2):
        dop_g[i, 0] = loc[i, 0, 0] * dop[0] + loc[i, 0, 1] * dop[1] + loc[
            i, 0, 2] * dop[2]
        dop_g[i, 1] = loc[i, 1, 0] * dop[0] + loc[i, 1, 1] * dop[1] + loc[
            i, 1, 2] * dop[2]
        dop_g[i, 2] = loc[i, 2, 0] * dop[0] + loc[i, 2, 1] * dop[1] + loc[
            i, 2, 2] * dop[2]

    # for RIXS
    thin, thout, phi = 30 / 180.0 * np.pi, 60 / 180.0 * np.pi, 0.0
    ein, eout = 11215.0, 11215.0  # eV
    kin, kout = edrixs.get_wavevector_rixs(thin, thout, phi, ein, eout)
    # polarization pi-pi and pi-sigma
    for key, alpha, beta in [('pp', 0, 0), ('ps', 0, np.pi)]:
        ei, ef = edrixs.dipole_polvec_rixs(thin, thout, phi, alpha, beta)
        T_i = np.zeros((2, 6, 6), dtype=np.complex)
        T_o = np.zeros((2, 6, 6), dtype=np.complex)
        for i in range(2):
            T_i[i] = (dop_g[i, 0] * ei[0] + dop_g[i, 1] * ei[1] +
                      dop_g[i, 2] * ei[2]) * np.exp(1j * np.dot(pos[i], kin))
            T_o[i] = np.exp(-1j * np.dot(pos[i], kout)) * np.conj(
                np.transpose(dop_g[i, 0] * ef[0] + dop_g[i, 1] * ef[1] +
                             dop_g[i, 2] * ef[2]))
        transop_rixs_i = np.zeros((24, 24), dtype=np.complex)
        transop_rixs_f = np.zeros((24, 24), dtype=np.complex)
        for i in range(2):
            off1, off2 = i * 6, 12 + i * 6
            transop_rixs_i[off1:off1 + 6, off2:off2 + 6] = T_i[i]
            transop_rixs_f[off2:off2 + 6, off1:off1 + 6] = T_o[i]
        edrixs.write_emat(transop_rixs_i, "rixs_" + key + "/transop_rixs_i.in")
        edrixs.write_emat(transop_rixs_f, "rixs_" + key + "/transop_rixs_f.in")

    # For XAS
    ei = np.array([1, 1, 1]) / np.sqrt(3.0)
    T_i = np.zeros((2, 6, 6), dtype=np.complex)
    for i in range(2):
        T_i[i] = dop_g[i, 0] * ei[0] + dop_g[i, 1] * ei[1] + dop_g[i,
                                                                   2] * ei[2]
    transop_xas = np.zeros((24, 24), dtype=np.complex128)
    for i in range(2):
        off1, off2 = i * 6, 12 + i * 6
        transop_xas[off1:off1 + 6, off2:off2 + 6] = T_i[i]
    edrixs.write_emat(transop_xas, "xas/transop_xas.in")
示例#3
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def get_transop():
    tmp = edrixs.get_trans_oper('t2gp')
    dipole = np.zeros((3, 28, 28), dtype=np.complex)
    for i in range(3):
        tmp[i] = edrixs.cb_op2(tmp[i], edrixs.tmat_c2j(1), edrixs.tmat_c2j(1))
        dipole[i, 0:6, 24:28] = tmp[i, 0:6, 2:6]

    # for RIXS
    thin, thout, phi = 45 / 180.0 * np.pi, 45 / 180.0 * np.pi, 0.0
    # polarization pi-pi and pi-sigma
    for key, alpha, beta in [('pp', 0, 0), ('ps', 0, np.pi)]:
        ei, ef = edrixs.dipole_polvec_rixs(thin, thout, phi, alpha, beta)
        transop_rixs_i = dipole[0] * ei[0] + dipole[1] * ei[1] + dipole[
            2] * ei[2]
        transop_rixs_f = np.conj(
            np.transpose(dipole[0] * ef[0] + dipole[1] * ef[1] +
                         dipole[2] * ef[2]))
        edrixs.write_emat(transop_rixs_i, "rixs_" + key + "/transop_rixs_i.in")
        edrixs.write_emat(transop_rixs_f, "rixs_" + key + "/transop_rixs_f.in")

    # For XAS
    ei = np.array([1, 1, 1]) / np.sqrt(3.0)
    transop_xas = dipole[0] * ei[0] + dipole[1] * ei[1] + dipole[2] * ei[2]
    edrixs.write_emat(transop_xas, "xas/transop_xas.in")
示例#4
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def ed():
    # 1-10: Ni-3d valence orbitals, 11-16: Ni-2p core orbitals
    # Single particle basis: complex shperical Harmonics
    ndorb, nporb, ntot = 10, 6, 16
    emat_i = np.zeros((ntot, ntot), dtype=np.complex)
    emat_n = np.zeros((ntot, ntot), dtype=np.complex)

    # 4-index Coulomb interaction tensor, parameterized by
    # Slater integrals, which are obtained from Cowan's code
    F2_d, F4_d = 7.9521, 4.9387
    # Averaged dd Coulomb interaction is set to be zero
    F0_d = edrixs.get_F0('d', F2_d, F4_d)
    G1_dp, G3_dp = 4.0509, 2.3037
    # Averaged dp Coulomb interaction is set to be zero
    F0_dp, F2_dp = edrixs.get_F0('dp', G1_dp, G3_dp), 7.33495
    umat_i = edrixs.get_umat_slater(
        'dp',
        F0_d,
        F2_d,
        F4_d,  # dd
        0,
        0,
        0,
        0,  # dp
        0,
        0)  # pp
    umat_n = edrixs.get_umat_slater(
        'dp',
        F0_d,
        F2_d,
        F4_d,  # dd
        F0_dp,
        F2_dp,
        G1_dp,
        G3_dp,  # dp
        0,
        0)  # pp

    # Atomic spin-orbit coupling
    zeta_d, zeta_p = 0.083, 11.24
    emat_i[0:ndorb, 0:ndorb] += edrixs.atom_hsoc('d', zeta_d)
    emat_n[0:ndorb, 0:ndorb] += edrixs.atom_hsoc('d', zeta_d)
    emat_n[ndorb:ntot, ndorb:ntot] += edrixs.atom_hsoc('p', zeta_p)

    # Tetragonal crystal field splitting terms,
    # which are first defined in the real cubic Harmonics basis,
    # and then transformed to complex shperical Harmonics basis.
    dt, ds, dq = 0.011428, 0.035714, 0.13
    tmp = np.zeros((5, 5), dtype=np.complex)
    tmp[0, 0] = 6 * dq - 2 * ds - 6 * dt  # d3z2-r2
    tmp[1, 1] = -4 * dq - 1 * ds + 4 * dt  # dzx
    tmp[2, 2] = -4 * dq - 1 * ds + 4 * dt  # dzy
    tmp[3, 3] = 6 * dq + 2 * ds - 1 * dt  # dx2-y2
    tmp[4, 4] = -4 * dq + 2 * ds - 1 * dt  # dxy
    tmp[:, :] = edrixs.cb_op(tmp, edrixs.tmat_r2c('d'))
    emat_i[0:ndorb:2, 0:ndorb:2] += tmp
    emat_i[1:ndorb:2, 1:ndorb:2] += tmp
    emat_n[0:ndorb:2, 0:ndorb:2] += tmp
    emat_n[1:ndorb:2, 1:ndorb:2] += tmp

    # Build Fock basis in its binary form
    basis_i = edrixs.get_fock_bin_by_N(ndorb, 8, nporb, nporb)
    basis_n = edrixs.get_fock_bin_by_N(ndorb, 9, nporb, nporb - 1)
    ncfg_i, ncfg_n = len(basis_i), len(basis_n)

    # Build many-body Hamiltonian in Fock basis
    hmat_i = np.zeros((ncfg_i, ncfg_i), dtype=np.complex)
    hmat_n = np.zeros((ncfg_n, ncfg_n), dtype=np.complex)
    hmat_i[:, :] += edrixs.two_fermion(emat_i, basis_i, basis_i)
    hmat_i[:, :] += edrixs.four_fermion(umat_i, basis_i)
    hmat_n[:, :] += edrixs.two_fermion(emat_n, basis_n, basis_n)
    hmat_n[:, :] += edrixs.four_fermion(umat_n, basis_n)

    # Do exact-diagonalization to get eigenvalues and eigenvectors
    eval_i, evec_i = np.linalg.eigh(hmat_i)
    eval_n, evec_n = np.linalg.eigh(hmat_n)

    # Build dipolar transition operators
    dipole = np.zeros((3, ntot, ntot), dtype=np.complex)
    T_abs = np.zeros((3, ncfg_n, ncfg_i), dtype=np.complex)
    T_emi = np.zeros((3, ncfg_i, ncfg_n), dtype=np.complex)
    tmp = edrixs.get_trans_oper('dp')
    for i in range(3):
        dipole[i, 0:ndorb, ndorb:ntot] = tmp[i]
        # First, in the Fock basis
        T_abs[i] = edrixs.two_fermion(dipole[i], basis_n, basis_i)
        # Then, transfrom to the eigenvector basis
        T_abs[i] = edrixs.cb_op2(T_abs[i], evec_n, evec_i)
        T_emi[i] = np.conj(np.transpose(T_abs[i]))

    return eval_i, eval_n, T_abs, T_emi
示例#5
0
    print("edrixs >>> Building Hamiltonian with a core-hole ...")
    eval_n = np.zeros((2, ncfgs_n), dtype=np.float64)
    evec_n = np.zeros((2, ncfgs_n, ncfgs_n), dtype=np.complex128)
    for i in range(2):
        hmat_n[i] += edrixs.two_fermion(emat_n[i], basis_n[i], basis_n[i])
        hmat_n[i] += edrixs.four_fermion(umat_n[i], basis_n[i])
        eval_n[i], evec_n[i] = scipy.linalg.eigh(hmat_n[i])
    print("edrixs >>> Done!")

    edrixs.write_tensor(eval_i, 'eval_i.dat')
    edrixs.write_tensor(eval_n, 'eval_n.dat')

    # Building transition operators
    print("edrixs >>> building transition operators ...")
    tran_ptod = edrixs.get_trans_oper('t2gp')
    for i in range(3):
        tran_ptod[i, :, :] = edrixs.cb_op2(tran_ptod[i],
                                           edrixs.tmat_c2r('t2g', True),
                                           edrixs.tmat_c2r('p', True))
    dipole_n = np.zeros((2, 3, norbs, norbs), dtype=np.complex128)
    dipole_n[0, :, 0:6, 12:18] = tran_ptod
    dipole_n[1, :, 6:12, 18:24] = tran_ptod
    trop_n = np.zeros((2, 3, ncfgs_n, ncfgs_i), dtype=np.complex128)
    for i in range(2):
        for j in range(3):
            trop_n[i, j] = edrixs.two_fermion(dipole_n[i, j], basis_n[i],
                                              basis_i)
            trop_n[i, j] = edrixs.cb_op2(trop_n[i, j], evec_n[i], evec_i)

    Ir_trop = np.zeros((2, 3, ncfgs_n, ncfgs_i), dtype=np.complex128)