2013-07-17 19:24:07 +02:00
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from pytriqs.lattice.tight_binding import *
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# Define the Bravais Lattice : a square lattice in 2d
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2014-05-31 19:12:21 +02:00
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BL = BravaisLattice(units = [(1,0,0) , (0,1,0) ])
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2013-07-17 19:24:07 +02:00
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# Prepare a nearest neighbour hopping on BL
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t = -1.00 # First neighbour Hopping
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tp = 0.0*t # Second neighbour Hopping
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# Hopping[ Displacement on the lattice] = [[t11,t12,t13....],[t21,t22,t23....],...,[....,tnn]]
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# where n=Number_Orbitals
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hop= { (1,0) : [[ t]],
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(-1,0) : [[ t]],
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(0,1) : [[ t]],
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(0,-1) : [[ t]],
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(1,1) : [[ tp]],
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(-1,-1): [[ tp]],
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(1,-1) : [[ tp]],
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(-1,1) : [[ tp]]}
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TB = TightBinding ( BL, hop)
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# Compute the density of states
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d = dos (TB, n_kpts= 500, n_eps = 101, name = 'dos')[0]
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# Plot the dos it with matplotlib
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from pytriqs.plot.mpl_interface import oplot
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from matplotlib import pylab as plt
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oplot(d,'-o')
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plt.xlim ( -5,5 )
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plt.ylim ( 0, 0.4)
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