include more plots in code

code/band_structures.py

@@ -122,3 +122,7 @@ def phonons_1d_2masses():
 def main():
     os.chdir('figures')
     fermi_dirac()
+    phonons_1d()
+    phonons_1d_2masses()
+    meff_1d_tb()
+    tight_binding_1d()