Merge branch 'patch-1' into 'master'

Use raw strings where needed

See merge request solidstate/lectures!1

code/band_structures.py

@@ -76,7 +76,7 @@ def tight_binding_1d():
     k = np.linspace(-pi, pi, 300)
     pyplot.plot(k, -np.cos(k))
     pyplot.xlabel('$ka$'); pyplot.ylabel('$E$')
-    pyplot.xticks([-pi, 0, pi], ['$-\pi$', 0, '$\pi$'])
+    pyplot.xticks([-pi, 0, pi], [r'$-\pi$', 0, r'$\pi$'])
     pyplot.yticks([-1, 0, 1], ['$E_0+2t$', '$E_0$', '$E_0-2t$'])
     pyplot.savefig('tight_binding_1d.svg')
 
@@ -90,7 +90,7 @@ def meff_1d_tb():
     pyplot.plot(k[meff < 0], meff[meff < 0], c=color)
     pyplot.ylim(-5, 5)
     pyplot.xlabel('$ka$'); pyplot.ylabel('$m_{eff}$')
-    pyplot.xticks([-pi, 0, pi], ['$-\pi$', 0, '$\pi$']);
+    pyplot.xticks([-pi, 0, pi], [r'$-\pi$', 0, r'$\pi$']);
     pyplot.savefig('meff_1d_tb.svg')
 
 
@@ -110,7 +110,7 @@ def phonons_1d_2masses():
         ax.plot(k, dispersion_2m(k), label='acoustic')
         ax.set_xlabel('$ka$')
         ax.set_ylabel(r'$\omega$')
-        pyplot.xticks([-pi, 0, pi], ['$-\pi$', '$0$', '$\pi$'])
+        pyplot.xticks([-pi, 0, pi], [r'$-\pi$', '$0$', r'$\pi$'])
         pyplot.yticks([], [])
         pyplot.vlines([-pi, pi], 0, 2.2, linestyles='dashed')
         pyplot.legend()