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Final: Fix task 4.3 except for some TODOs and comments

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Kees van Kempen
2022-04-04 08:27:29 +02:00
parent 78ad9d9660
commit c608809edf
1 changed files with 16 additions and 19 deletions
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35
Final/Final - Tight-binding propagation method.ipynb
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@ -1339,6 +1339,7 @@
" # And that indeed t[0] = 0*tau = 0.\n", " # And that indeed t[0] = 0*tau = 0.\n",
" assert np.allclose(t[0], 0)\n", " assert np.allclose(t[0], 0)\n",
" \n", " \n",
" # TODO: What should the dtype be, should it be complex?\n",
" c = np.zeros(t.shape + c0.shape, dtype=c0.dtype)\n", " c = np.zeros(t.shape + c0.shape, dtype=c0.dtype)\n",
" c[0] = c0\n", " c[0] = c0\n",
" \n", " \n",
@ -1440,16 +1441,7 @@
"task": false "task": false
} }
}, },
"outputs": [ "outputs": [],
{
"name": "stderr",
"output_type": "stream",
"text": [
"/tmp/ipykernel_2000248/327551893.py:14: ComplexWarning: Casting complex values to real discards the imaginary part\n",
" c[j] = U@c[j - 1]\n"
]
}
],
"source": [ "source": [
"n = 100\n", "n = 100\n",
"# TODO: Should one be able to pass a through everything?\n", "# TODO: Should one be able to pass a through everything?\n",
@ -1460,15 +1452,18 @@
"\n", "\n",
"H = TBHamiltonian(n, sigma)\n", "H = TBHamiltonian(n, sigma)\n",
"U = getU_exact(tau, H)\n", "U = getU_exact(tau, H)\n",
"#c0 = np.zeros(n, dtype=np.complex128)\n", "# TODO: Is c0 complex?\n",
"c0 = np.zeros(n)\n", "c0 = np.zeros(n, dtype=np.complex128)\n",
"#c0 = np.zeros(n)\n",
"c0[n//2] = 1\n", "c0[n//2] = 1\n",
"\n", "\n",
"c = timePropagate(U, c0, t)\n", "c = timePropagate(U, c0, t)\n",
"xi = atomic_positions(n, a)\n", "xi = atomic_positions(n, a)\n",
"psi = c@atomic_basis(x, xi, sigma).T\n", "x = np.linspace(-1, 101, 150)\n",
"\n", "# TODO: Does real-space wavefunction mean that it should be real or\n",
"x = np.linspace(-1, 11, 150)" "# that we take the real part?\n",
"psi = np.real(c@atomic_basis(x, xi, sigma).T)\n",
"\n"
] ]
}, },
{ {
@ -1477,6 +1472,8 @@
"metadata": {}, "metadata": {},
"outputs": [], "outputs": [],
"source": [ "source": [
"psi\n",
"\n",
"# This cell can be deleted!\n", "# This cell can be deleted!\n",
"x = np.linspace(-1, 11, 150)\n", "x = np.linspace(-1, 11, 150)\n",
"xi = atomic_positions(n, a)\n", "xi = atomic_positions(n, a)\n",
@ -1488,8 +1485,8 @@
"#print(psi)\n", "#print(psi)\n",
"psi.shape\n", "psi.shape\n",
"#psi[t][x]\n", "#psi[t][x]\n",
"plt.plot(x, psi[30])\n", "plt.plot(x, psi[20])\n",
"print(psi[2].shape, x.shape)" "print(psi[100].shape, x.shape)"
] ]
}, },
{ {
@ -1521,8 +1518,8 @@
"# create a figure for the animation\n", "# create a figure for the animation\n",
"fig = plt.figure()\n", "fig = plt.figure()\n",
"plt.grid(True)\n", "plt.grid(True)\n",
"plt.xlim(-1, 11) # fix x limits\n", "plt.xlim(-1, 101) # fix x limits\n",
"plt.ylim(-1e-6, 1e-6) # fix y limits\n", "plt.ylim(-.5, .6) # fix y limits\n",
"plt.xlabel('$x$')\n", "plt.xlabel('$x$')\n",
"plt.ylabel('$\\\\psi(t, x)$')\n", "plt.ylabel('$\\\\psi(t, x)$')\n",
"\n", "\n",