Example #1
0
def ipt_u_tp(u_int, tp, beta, seed='ins'):
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=2**8))
    tau, w_n = gf.tau_wn_setup(
        dict(BETA=beta, N_MATSUBARA=max(2**ceil(log(8 * beta) / log(2)), 256)))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)
    if seed == 'ins':
        giw_d, giw_o = 1 / (1j * w_n + 4j / w_n), np.zeros_like(w_n) + 0j

    giw_d, giw_o, loops = dimer.ipt_dmft_loop(
        beta, u_int, tp, giw_d, giw_o, tau, w_n, 1e-7)
    g0iw_d, g0iw_o = dimer.self_consistency(
        1j * w_n, 1j * giw_d.imag, giw_o.real, 0., tp, 0.25)
    siw_d, siw_o = ipt.dimer_sigma(u_int, tp, g0iw_d, g0iw_o, tau, w_n)

    return giw_d, giw_o, siw_d, siw_o, g0iw_d, g0iw_o, w_n
Example #2
0
def energies(beta, filestr='SB_PM_B{}.h5'):
    """returns the potential, and kinetic energy

    Parameters
    ----------
    beta : float, inverse temperature
    filestr : string, results file name, beta is replaced in format

    Returns
    -------
    tuple of 3 ndarrays
        Contains, potential energy, Kinetic energy, values of U
    """
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=beta))
    giw_free = gf.greenF(w_n)
    e_mean = ipt.e_mean(beta)
    ekin = []
    epot = []
    with h5.File(filestr.format(beta), 'r') as results:
        for u_str in results:
            last_iter = results[u_str].keys()[-1]
            _, giw = get_giw(results[u_str], last_iter, tau, w_n)
            siw = get_sigmaiw(results[u_str], last_iter, tau, w_n)

            u_int = float(u_str[1:])

            epot.append(ipt.epot(giw, siw, u_int, beta, w_n))
            ekin.append(ipt.ekin(giw, siw, beta, w_n, e_mean, giw_free))
        ur = np.array([float(u_str[1:]) for u_str in results])

    return np.array(epot), np.array(ekin), ur
Example #3
0
def show_conv(beta, u_int, filestr='SB_{simt}_B{beta}', n_freq=5, xlim=2, skip=5, simt='PM'):
    """Plot the evolution of the Green's function in DMFT iterations"""
    freq_arr = []
    sim_dir = os.path.join(filestr.format(
        beta=beta, simt=simt), 'U' + str(u_int))
    iterations = sorted(
        [it for it in os.listdir(sim_dir) if 'it' in it])[skip:]
    with open(sim_dir + '/setup', 'r') as read:
        setup = json.load(read)
    tau, w_n = gf.tau_wn_setup(setup)

    _, axes = plt.subplots(1, 2, figsize=(13, 8), sharey=True)
    for step in iterations:
        giw, caste = get_giw(sim_dir, [step], tau, w_n, setup)
        if len(giw.shape) > 1:
            axes[0].plot(w_n, giw[0].real, 'gs:', w_n, giw[0].imag, 'bo:')
            freq_arr.append(
                np.array([giw[0].real[:n_freq], giw[0].imag[:n_freq]]))
        else:
            axes[0].plot(w_n, giw.imag)
            freq_arr.append(giw.imag[:n_freq])

    freq_arr = np.asarray(freq_arr).T
    for num, freqs in enumerate(freq_arr):
        axes[1].plot(freqs.T, 'o-.', label=str(num))
    graf = r'$G(i\omega_n)$'

    label_convergence(beta, u_int, axes, graf, n_freq, xlim)

    return axes
Example #4
0
def get_giw(sim_dir, iteration_slice, tau=None, w_n=None, setup=None):
    r"""Recovers with Fourier Transform G_iw from H5 file

    Parameters
    ----------
    h5parent : hdf5 group to go
    iteration_slice : list of iteration names to average over
    tau : 1D real array time slices of HF data
    w_n : 1D real array matsubara frequencies

    Returns
    -------
    tuple : :math:`G(\tau)`, :math:`G(i\omega_n)`
    """

    recovered_sim_info = False
    if None in (tau, w_n, setup):
        with open(sim_dir + '/setup', 'r') as read:
            setup = json.load(read)
        tau, w_n = gf.tau_wn_setup(setup)
        recovered_sim_info = True

    gtau = averager(sim_dir, 'gtau.npy', iteration_slice)
    giw = gf.gt_fouriertrans(gtau, tau, w_n,
                             gf_tail(gtau, setup['U'], setup['MU']))

    if recovered_sim_info:
        return giw, gtau, tau, w_n, setup
    else:
        return giw, gtau
Example #5
0
def estimate_zero_w_sigma_T_vs_U(tp, u_range, temp, phase):
    sd_zew, so_zew = [], []
    u_range = u_range if phase == 'met' else u_range[::-1]

    save_file = 'dimer_ipt_{}_Z_tp{:.2}.npy'.format(phase, tp)
    if os.path.exists(save_file):
        return np.load(save_file)

    for T in temp:
        beta = 1 / T
        tau, w_n = gf.tau_wn_setup(
            dict(BETA=beta, N_MATSUBARA=max(2**ceil(log(6 * beta) / log(2)), 256)))
        filestr = 'disk/phase_Dimer_ipt_{}_tp{:.2}/B{:.5}/giw.npy'.format(
            phase, tp, beta)
        gfs = np.load(filestr)

        for i, u_int in enumerate(u_range):
            giw_d, giw_o = 1j * gfs[i][0], gfs[i][1]
            g0iw_d, g0iw_o = dimer.self_consistency(
                1j * w_n, giw_d, giw_o, 0., tp, 0.25)
            siw_d, siw_o = ipt.dimer_sigma(u_int, tp, g0iw_d, g0iw_o, tau, w_n)
            sd_zew.append(np.polyfit(w_n[:2], siw_d[:2].imag, 1))
            so_zew.append(np.polyfit(w_n[:2], siw_o[:2].real, 1))

    sd_zew = np.array(sd_zew).reshape(len(temp), len(u_range), -1)
    so_zew = np.array(so_zew).reshape(len(temp), len(u_range), -1)
    np.save(save_file, (sd_zew, so_zew))

    return sd_zew, so_zew
Example #6
0
def loop_tp_u(tprange, u_range, beta, filestr, seed='mott gap'):

    save_dir = filestr.format(beta)
    if np.allclose(tprange, tprange[0]) and 'tp' not in save_dir:
        save_dir = os.path.join(save_dir, 'tp' + str(tprange[0]))
    elif np.allclose(u_range, u_range[0]):
        save_dir = os.path.join(save_dir, 'U' + str(u_range[0]))

    if not os.path.exists(save_dir):
        os.makedirs(save_dir)

    setup = {
        'beta': beta,
        'tprange': tprange.tolist(),
        'u_range': u_range.tolist()
    }
    with open(save_dir + '/setup', 'w') as conf:
        json.dump(setup, conf, indent=2)


###############################################################################

    tau, w_n = gf.tau_wn_setup(
        dict(BETA=beta, N_MATSUBARA=max(2**ceil(log(6 * beta) / log(2)), 256)))
    giw_d, giw_o = dimer.gf_met(w_n, 0., tprange[0], 0.5, 0.)
    if seed == 'mott gap':
        giw_d, giw_o = 1 / (1j * w_n - 4j / w_n), np.zeros_like(w_n) + 0j

    giw_s = []
    for tp, u_int in zip(tprange, u_range):
        giw_d, giw_o, loops = dimer.ipt_dmft_loop(beta, u_int, tp, giw_d,
                                                  giw_o, tau, w_n,
                                                  1 / 5 / beta)
        giw_s.append((giw_d.imag, giw_o.real))
    np.save(save_dir + '/giw', np.array(giw_s))
Example #7
0
def plot_zero_w(function_array, iter_range, tp, betarange, ax, color):
    """Plot the zero frequency extrapolation of a function
    Parameters
    ----------
    function_array: real ndarray
      contains the function (G, Sigma) to linearly fit over 2 first frequencies
    iter_range: list floats
      values of changing variable U or tp
    berarange: real ndarray 1D, values of beta
    entry: 0, 1 corresponds to diagonal or off-diagonal entry of function
    label_head: string for label
    ax, dx: matplotlib axis to plot in
    """

    sig_11_0 = []
    rtp = []
    for j, u in enumerate(iter_range):
        sig_11_0.append([])
        rtp.append([])
        for i, beta in list(enumerate(betarange)):
            tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=2))
            sig_11_0[j].append(np.polyfit(
                w_n, function_array[j][i][0][:2], 1)[1])
            rtp[j].append(np.polyfit(w_n, function_array[j][i][1][:2], 1)[1])

        ax[0].plot(1 / BETARANGE, -np.array(sig_11_0[j]), color, label=str(u))
        ax[1].plot(1 / BETARANGE, tp + np.array(rtp[j]), color, label=str(u))
    ax[0].set_ylabel(r'$-\Im m \Sigma_{11}(w=0)$')
    ax[1].set_ylabel(r'$t_\perp + \Re e\Sigma_{12}(w=0)$')
    ax[1].set_xlabel('$T/D$')
    ax[1].set_xlim([min(temp), max(temp)])

    return np.array(sig_11_0)
Example #8
0
def test_ipt_dimer_pm_g(u_int, result, beta=50.):
    tau, w_n = tau_wn_setup(dict(BETA=beta, N_MATSUBARA=256))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0, 0.5, 0.)
    giw_d = dimer.ipt_dmft_loop(beta, u_int, 0, giw_d, giw_o, tau, w_n,
                                1e-5)[0][:64]

    assert np.allclose(result, giw_d, atol=3e-3)
Example #9
0
def loop_u_tp(u_range, tp_range, beta, seed='mott gap'):
    """Solves IPT dimer and return Im Sigma_AA, Re Simga_AB

    returns list len(betarange) x 2 Sigma arrays
"""
    tau, w_n = gf.tau_wn_setup(
        dict(BETA=beta, N_MATSUBARA=max(2**ceil(log(4 * beta) / log(2)), 256)))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)
    if seed == 'I':
        giw_d, giw_o = 1 / (1j * w_n - 4j / w_n), np.zeros_like(w_n) + 0j

    sigma_iw = []
    iterations = []
    for tp, u_int in zip(tp_range, u_range):
        giw_d, giw_o, loops = dimer.ipt_dmft_loop(beta, u_int, tp, giw_d,
                                                  giw_o, tau, w_n, 1e-3)
        iterations.append(loops)
        g0iw_d, g0iw_o = dimer.self_consistency(1j * w_n, 1j * giw_d.imag,
                                                giw_o.real, 0., tp, 0.25)
        siw_d, siw_o = ipt.dimer_sigma(u_int, tp, g0iw_d, g0iw_o, tau, w_n)
        sigma_iw.append((siw_d.imag, siw_o.real))

    print(np.array(iterations))

    return sigma_iw
Example #10
0
def test_selfconsistency(tp):
    """Check that the Bethe lattice self-consistency is working"""
    _, w_n = tau_wn_setup(dict(BETA=100., N_MATSUBARA=400))
    giwd, giwo = dimer.gf_met(w_n, 0., tp, 0.5, 0.)
    g0iwd, g0iwo = dimer.self_consistency(1j * w_n, giwd, giwo, 0., tp, 0.25)
    assert np.allclose(giwd, g0iwd)
    assert np.allclose(giwo, g0iwo)
def loop_u_tp(u_range, tprange, beta, seed='mott gap'):
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=max(5 * beta, 256)))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)
    if seed == 'mott gap':
        giw_d, giw_o = 1 / (1j * w_n + 4j / w_n), np.zeros_like(w_n) + 0j

    giw_s = []
    sigma_iw = []
    ekin, epot = [], []
    iterations = []
    for u_int, tp in zip(u_range, tprange):
        giw_d, giw_o, loops = dimer.ipt_dmft_loop(beta, u_int, tp, giw_d,
                                                  giw_o, tau, w_n)
        giw_s.append((giw_d, giw_o))
        iterations.append(loops)
        g0iw_d, g0iw_o = dimer.self_consistency(1j * w_n, 1j * giw_d.imag,
                                                giw_o.real, 0., tp, 0.25)
        siw_d, siw_o = ipt.dimer_sigma(u_int, tp, g0iw_d, g0iw_o, tau, w_n)
        sigma_iw.append((siw_d.copy(), siw_o.copy()))

        ekin.append(dimer.ekin(giw_d, giw_o, w_n, tp, beta))

        epot.append(
            dimer.epot(giw_d, w_n, beta, u_int**2 / 4 + tp**2, ekin[-1], u_int)
            / 4)  # last division because I want per spin epot

    print(np.array(iterations))

    return np.array(giw_s), np.array(sigma_iw), np.array(ekin), np.array(
        epot), w_n
Example #12
0
def free_energy_change(beta, u_int, mix_grid):

    tau, w_n = tau_wn_setup(dict(BETA=beta, N_MATSUBARA=2**11))

    ig_iwn, is_iwn = dmft_loop(u_int,
                               0.5,
                               -1.j / (w_n - 1 / w_n),
                               w_n,
                               tau,
                               conv=1e-10)

    mg_iwn, ms_iwn = dmft_loop(u_int, 0.5, greenF(w_n), w_n, tau, conv=1e-10)

    solution_diff = mg_iwn - ig_iwn

    integrand = []
    for l in mix_grid:
        g_in = mix(mg_iwn, ig_iwn, l)
        g_grad = one_loop(g_in, 0.5, U, w_n, tau) - g_in
        integrand.append(np.dot(g_grad, solution_diff).real / beta)

    return np.array([0] + [
        trapz(integrand[:i], mix_grid[:i])
        for i in range(2,
                       len(mix_grid) + 1)
    ])
Example #13
0
def hysteresis(beta, u_range):
    log_g_sig = []
    tau, w_n = tau_wn_setup(dict(BETA=beta, N_MATSUBARA=beta))
    g_iwn = greenF(w_n)
    for u_int in u_range:
        g_iwn, sigma = dmft_loop(u_int, 0.5, g_iwn, w_n, tau)
        log_g_sig.append((g_iwn, sigma))
    return log_g_sig
Example #14
0
def hysteresis(beta, D_range):
    log_g_sig = []
    tau, w_n = tau_wn_setup(dict(BETA=beta, N_MATSUBARA=2**11))
    g_iwn = greenF(w_n, D=1)
    for D in D_range:
        g_iwn, sigma = dmft_loop(1, D / 2, g_iwn, w_n, tau)
        log_g_sig.append((g_iwn, sigma))
    return log_g_sig
Example #15
0
def extract_double_occupation(beta, u_range):
    docc = []
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=beta))
    g_iwn = gf.greenF(w_n)
    for u_int in u_range:
        g_iwn, sigma = ipt.dmft_loop(u_int, 0.5, g_iwn, w_n, tau, conv=1e-4)
        docc.append(ipt.epot(g_iwn, sigma, u_int, beta, w_n) * 2 / u_int)
    return np.array(docc)
Example #16
0
def setup_PM_sim(parms):
    tau, w_n = tau_wn_setup(parms)
    gw = greenF(w_n, mu=parms['MU'], D=2 * parms['t'])
    gt = gw_invfouriertrans(gw, tau, w_n)
    gt = interpol(gt, parms['n_tau_mc'])
    parms['dtau_mc'] = parms['BETA'] / parms['n_tau_mc']
    v = ising_v(parms['dtau_mc'], parms['U'], L=parms['n_tau_mc'])

    return tau, w_n, gt, gw, v
Example #17
0
def test_ipt_pm_g(u_int, result, beta=50., n_tau=2**11, n_matsubara=64):
    parms = {'BETA': beta, 'N_TAU': n_tau, 'N_MATSUBARA': n_matsubara,
             't': 0.5, 'MU': 0, 'U': u_int,
             }
    tau, w_n = tau_wn_setup(parms)
    g_iwn0 = greenF(w_n, D=2*parms['t'])
    g_iwn_log, sigma_iwn = ipt_imag.dmft_loop(100, parms['U'], parms['t'], g_iwn0, w_n, tau)

    assert np.allclose(result, g_iwn_log[-1][32:], atol=1e-3 )
Example #18
0
def setup_PM_sim(parms):
    tau, w_n = tau_wn_setup(parms)
    gw = greenF(w_n, mu=parms['MU'], D=2*parms['t'])
    gt = gw_invfouriertrans(gw, tau, w_n)
    gt = interpol(gt, parms['n_tau_mc'])
    parms['dtau_mc'] = parms['BETA']/parms['n_tau_mc']
    v = ising_v(parms['dtau_mc'], parms['U'], L=parms['n_tau_mc'])

    return tau, w_n, gt, gw, v
Example #19
0
def test_fourier_trasforms(chempot, beta=50., n_matsubara=128):
    """Test the tail improved fourier transforms"""
    parms = {'BETA': beta, 'N_MATSUBARA': n_matsubara}
    tau, w_n = gf.tau_wn_setup(parms)
    giw = gf.greenF(w_n, mu=chempot)

    for gwr in [giw, np.array([giw, giw])]:
        g_tau = gf.gw_invfouriertrans(gwr, tau, w_n, [1., -chempot, 0.25])
        g_iomega = gf.gt_fouriertrans(g_tau, tau, w_n, [1., -chempot, 0.25])
        assert np.allclose(gwr, g_iomega)
Example #20
0
def test_fourier_trasforms(chempot, beta=50., n_tau=2**11, n_matsubara=64):
    """Test the tail improved fourier transforms"""
    parms = {'BETA': beta, 'N_TAU': n_tau, 'N_MATSUBARA': n_matsubara}
    tau, w_n = tau_wn_setup(parms)
    gw = greenF(w_n, mu=chempot)

    for gwr in [gw, np.array([gw, gw])]:
        g_tau = gw_invfouriertrans(gwr, tau, w_n)
        g_iomega = gt_fouriertrans(g_tau, tau, w_n)
        assert np.allclose(gwr, g_iomega)
Example #21
0
def test_fourier_trasforms(chempot, beta=50., n_tau=2**11, n_matsubara=64):
    """Test the tail improved fourier transforms"""
    parms = {'BETA': beta, 'N_TAU': n_tau, 'N_MATSUBARA': n_matsubara}
    tau, w_n = tau_wn_setup(parms)
    gw = greenF(w_n, mu=chempot)

    for gwr in [gw, np.array([gw, gw])]:
        g_tau = gw_invfouriertrans(gwr, tau, w_n)
        g_iomega = gt_fouriertrans(g_tau, tau, w_n)
        assert np.allclose(gwr, g_iomega)
Example #22
0
def collect_bined_saves():
    binede_dat = glob('gtau_bin_*')
    G = np.array([np.load(dfile) for dfile in binede_dat])
    gtau = G.mean(1)
    tau, w_n = gf.tau_wn_setup(dict(BETA=32., N_MATSUBARA=32))
    fw = gf.matsubara_freq(32., 64, -63)

    giw = gf.gt_fouriertrans(gtau, tau, w_n, [1., 0., .25 + 2.5**2 / 4])

    sgiw = np.concatenate((giw.conj().T[::-1], giw.T))
    np.savez('bined', w_n=fw, giw=sgiw)
Example #23
0
def test_GF():
    """Test the Matrix product and Matrix inversion of a 2x2 Matrix
    which for the case of the dimer has a symmetric structure in which
    only requires the first row"""

    _, w_n = tau_wn_setup(dict(BETA=100., N_MATSUBARA=400))
    giwd, giwo = dimer.gf_met(w_n, 0., 0.25, 0.5, 0.)
    inv_giwd, inv_giwo = dimer.mat_inv(giwd, giwo)
    one, zero = dimer.mat_mul(inv_giwd, inv_giwo, giwd, giwo)
    assert np.allclose(one, 1.)
    assert np.allclose(zero, 0.)
Example #24
0
def setup_PM_sim(parms):
    """Setup the default state for a Paramagnetic simulation"""
    tau, w_n = tau_wn_setup(parms)
    giw = greenF(w_n, mu=parms['MU'], D=2 * parms['t'])
    gtau = gw_invfouriertrans(giw, tau, w_n)
    parms['dtau_mc'] = tau[1]
    intm = interaction_matrix(parms.get('BANDS', 1))
    v = ising_v(parms['dtau_mc'], parms['U'],
                len(tau) * parms['SITES'], intm.shape[1],
                parms['spin_polarization'])

    return tau, w_n, gtau, giw, v, intm
Example #25
0
def ipt_u_tp(u_int, tp, beta, seed="ins"):
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=1024))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)
    if seed == "ins":
        giw_d, giw_o = 1 / (1j * w_n + 4j / w_n), np.zeros_like(w_n) + 0j

    giw_d, giw_o, loops = dimer.ipt_dmft_loop(
        beta, u_int, tp, giw_d, giw_o, tau, w_n, 1e-12)
    g0iw_d, g0iw_o = dimer.self_consistency(
        1j * w_n, 1j * giw_d.imag, giw_o.real, 0., tp, 0.25)
    siw_d, siw_o = ipt.dimer_sigma(u_int, tp, g0iw_d, g0iw_o, tau, w_n)

    return giw_d, giw_o, siw_d, siw_o, g0iw_d, g0iw_o, w_n
Example #26
0
def test_ipt_pm_g(u_int, result, beta=50., n_matsubara=64):
    """Test the solution of the single band impurity problem"""
    parms = {
        'BETA': beta,
        'N_MATSUBARA': n_matsubara,
        't': 0.5,
        'MU': 0,
        'U': u_int,
    }
    tau, w_n = tau_wn_setup(parms)
    g_iwn0 = greenF(w_n, D=2 * parms['t'])
    g_iwn, _ = ipt_imag.dmft_loop(parms['U'], parms['t'], g_iwn0, w_n, tau)

    assert np.allclose(result, g_iwn, atol=3e-3)
Example #27
0
def loop_urange(urange, tp, beta):
    ekin, epot = [], []
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=2**10))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)

    for u_int in urange:
        giw_d, giw_o, _ = dimer.ipt_dmft_loop(beta, u_int, tp, giw_d, giw_o,
                                              tau, w_n, 1e-4)

        ekin.append(dimer.ekin(giw_d, giw_o, w_n, tp, beta))
        epot.append(
            dimer.epot(giw_d, w_n, beta, u_int**2 / 4 + tp**2 + 0.25, ekin[-1],
                       u_int))

    return np.array(ekin), np.array(epot)
Example #28
0
def test_ipt_pm_g(u_int, result, beta=50., n_tau=2**11, n_matsubara=64):
    parms = {
        'BETA': beta,
        'N_TAU': n_tau,
        'N_MATSUBARA': n_matsubara,
        't': 0.5,
        'MU': 0,
        'U': u_int,
    }
    tau, w_n = tau_wn_setup(parms)
    g_iwn0 = greenF(w_n, D=2 * parms['t'])
    g_iwn_log, sigma_iwn = ipt_imag.dmft_loop(100, parms['U'], parms['t'],
                                              g_iwn0, w_n, tau)

    assert np.allclose(result, g_iwn_log[-1][32:], atol=1e-3)
Example #29
0
def dos_plot(BETA, tp, filestr, ax=None):
    """Plots double occupation"""
    if ax is None:
        _, ax = plt.subplots()
    with h5.File(filestr.format(tp=tp, BETA=BETA), 'r') as results:
        fl_dos = []
        tau, w_n = gf.tau_wn_setup(dict(BETA=BETA, N_MATSUBARA=BETA))
        for u_str in results:
            lastit = results[u_str].keys()[-1]
            giwd, _ = get_giw(results[u_str], lastit, tau, w_n)
            fl_dos.append(-1. / np.pi * gf.fit_gf(w_n[:3], giwd.imag)(0.))

        u_range = np.array([float(u_str[1:]) for u_str in results.keys()])
        ax.scatter(u_range, fl_dos, s=120, marker='>', vmin=0, vmax=2. / np.pi)
    ax.set_title('Hysteresis loop of the \n density of states')
    ax.set_ylabel(r'$A(\omega=0)$')
    ax.set_xlabel('U/D')
def loop_u_tp(u_range, tprange, beta, seed='mott gap'):
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=max(5 * beta, 256)))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)
    if seed == 'mott gap':
        giw_d, giw_o = 1 / (1j * w_n + 4j / w_n), np.zeros_like(w_n) + 0j

    sigma_iw = []
    for u_int, tp in zip(u_range, tprange):
        giw_d, giw_o, loops = dimer.ipt_dmft_loop(
            beta, u_int, tp, giw_d, giw_o, tau, w_n)
        g0iw_d, g0iw_o = dimer.self_consistency(
            1j * w_n, 1j * giw_d.imag, giw_o.real, 0., tp, 0.25)
        siw_d, siw_o = ipt.dimer_sigma(u_int, tp, g0iw_d, g0iw_o, tau, w_n)
        sigma_iw.append((siw_d.copy(), siw_o.copy()))
        print(seed, ' U', u_int, ' tp: ', tp, ' loops: ', loops)

    return np.array(sigma_iw), w_n
def loop_u_tp(u_range, tprange, beta, seed='mott gap'):
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=256))
    giw_d, giw_o = dimer.gf_met(w_n, 0., 0., 0.5, 0.)
    if seed == 'ins':
        giw_d, giw_o = 1 / (1j * w_n + 4j / w_n), np.zeros_like(w_n) + 0j

    sols = [dmft_solve(giw_d, giw_o, u_int, tp, beta, tau, w_n)
            for u_int, tp in zip(u_range, tprange)]
    giw_s = np.array([g[0] for g in sols])
    sigma_iw = np.array([g[1] for g in sols])
    ekin = np.array([g[2] for g in sols])
    epot = np.array([g[3] for g in sols])
    iterations = np.array([g[4] for g in sols])

    print(iterations)

    return giw_s, sigma_iw, ekin, epot, w_n
Example #32
0
def get_giw(filestr, tau=None, w_n=None, setup=None):
    """Recovers with Fourier Transform G_iw and G_tau from npy file

    Parameters
    ----------
    filestr : string
            file with array data G(tau)
    setup : dictionary about simulation parameters
    tau : real float array
            Imaginary time points
    w_n : real float array
            fermionic matsubara frequencies. Only use the positive ones

    Returns
    -------
    tuple complex ndarray (giw, gtau)
            Interacting Greens function in matsubara frequencies
            and original Imaginary time. Entries are list ordered and
            not in matrix shape

    See also
    --------
    get_sigmaiw
    """

    recovered_sim_info = False
    if None in (tau, w_n, setup):
        sim_dir = os.path.dirname(os.path.dirname(os.path.abspath(filestr)))
        with open(sim_dir + '/setup', 'r') as read:
            setup = json.load(read)
        tau, w_n = gf.tau_wn_setup(setup)
        recovered_sim_info = True

    gtau = np.load(filestr)
    mu, tp, u_int = setup['MU'], setup['tp'], setup['U']
    giw = gf.gt_fouriertrans(gtau.reshape(2, 2, -1), tau, w_n,
                             gf_tail(gtau.reshape(2, 2, -1), u_int, mu, tp))

    if recovered_sim_info:
        return giw.reshape(4, -1), gtau, tau, w_n, setup
    else:
        return giw.reshape(4, -1), gtau
Example #33
0
def plot_zero_w(function_array, iter_range, beta, entry, label_head, ax, dx):
    """Plot the zero frequency extrapolation of a function
    Parameters
    ----------
    function_array: real ndarray
      contains the function (G, Sigma) to linearly fit over 2 first frequencies
    iter_range: list floats
      values of changing variable U or tp
    berarange: real ndarray 1D, values of beta
    entry: 0, 1 corresponds to diagonal or off-diagonal entry of function
    label_head: string for label
    ax, dx: matplotlib axis to plot in
    """
    tau, w_n = gf.tau_wn_setup(dict(BETA=beta, N_MATSUBARA=20))

    dat = []
    for j, u in enumerate(iter_range):
        dat.append(np.polyfit(w_n[:2], function_array[j][entry][:2], 1))
    ax.plot(iter_range, -np.array(dat)[:, 1], label=label_head)
    dx.plot(iter_range, -np.array(dat)[:, 0], label=label_head)
Example #34
0
from dmft.common import greenF, tau_wn_setup
from dmft.twosite import matsubara_Z

import numpy as np
import matplotlib.pylab as plt

U = np.linspace(0, 2.7, 36)
U = np.concatenate((U, U[-2:11:-1]))

parms = {'MU': 0, 't': 0.5, 'N_TAU': 2**10, 'N_MATSUBARA': 2**7}
lop_g=[]
for beta in [16, 25, 50]:
    u_zet = []
    parms['BETA'] = beta
    tau, w_n = tau_wn_setup(parms)
    g_iwn0 = greenF(w_n, D=2*parms['t'])
    for u_int in U:
        mix = 0.4 if u_int > 1.5 else 1
        g_iwn_log, sigma = ipt_imag.dmft_loop(100, u_int, parms['t'], g_iwn0, w_n, tau, mix)
        g_iwn0 = g_iwn_log[-1]
        lop_g.append(g_iwn_log)
        u_zet.append(matsubara_Z(sigma.imag, beta))

    plt.plot(U, u_zet, label='$\\beta={}$'.format(beta))
plt.title('Hysteresis loop of the quasiparticle weigth')
plt.legend()
plt.ylabel('Z')
plt.xlabel('U/D')