.. _sphx_glr_dimer_lattice_plot_dimer_bethe.py:


Dimer Bethe lattice
===================

Non interacting dimer of a Bethe lattice



.. code-block:: python


    import numpy as np
    import matplotlib.pyplot as plt
    import dmft.common as gf
    import dmft.dimer as dimer








Real frequency spectral function
================================



.. code-block:: python


    w = 1e-3j + np.linspace(-4, 4, 2**10)
    mu, t = 0, 0.5
    t2 = t**2

    plt.figure()
    for tab in [0, 0.25, 0.5, 0.75, 1.1]:

        Gd, Gc = dimer.gf_met(-1j * w, mu, tab, t, 0.)
        Gd, Gc = dimer.self_consistency(w, Gd, Gc, mu, tab, t2)

        plt.plot(w.real, -Gd.imag / np.pi, label=r'$t_c={}$'.format(tab))
    #    plt.plot(w.real, Gd.real, label=r'$\Re e Gd$')
    #    plt.plot(w.real, Gc.real, label=r'$\Re e Gc$')
    #    plt.plot(w.real, Gc.imag, label=r'$\Im m Gc$')

    plt.legend(loc=0)
    plt.xlabel(r'$\omega$')
    plt.ylabel(r'$A(\omega)$')





.. image:: /dimer_lattice/images/sphx_glr_plot_dimer_bethe_001.png
    :align: center




Matsubara frequency Green's function
====================================



.. code-block:: python


    w_n = gf.matsubara_freq(50., 512)
    iw_n = 1j * w_n
    plt.figure()
    for tab in [0, 0.25, 0.5, 0.75, 1.1]:

        Gd, Gc = dimer.gf_met(w_n, mu, tab, t, 0.)
        Gd, Gc = dimer.self_consistency(iw_n, Gd, Gc, mu, tab, t2)

        plt.plot(w_n, Gd.imag, 'o-', label=r'$t_c={}$'.format(tab))

    plt.legend(loc=0)
    plt.xlim([0, 6.5])
    plt.xlabel(r'$i\omega_n$')
    plt.ylabel(r'$G(i\omega_n)$')



.. image:: /dimer_lattice/images/sphx_glr_plot_dimer_bethe_002.png
    :align: center




**Total running time of the script:** ( 0 minutes  0.183 seconds)



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     :download:`Download Python source code: plot_dimer_bethe.py <plot_dimer_bethe.py>`



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