I need to calculate the group velocity of the guided mode in 1-D line defect photonic crystal waveguide. When I extract the group velocities using grep I'm getting velocities for different k-points and different band gaps
tevelocity:, 1, #(0.0 0.0 0.0), #(3.08591790567814e-8 -3.17361897850985e-10 0.0), #(-3.18411484190156e-8 8.71342196808855e-11 0.0), #(1.84721203025619e-8 8.50943462313198e-11 0.0), #(-1.74134645752838e-8 -8.68616295160761e-11 0.0), #(-3.7772400907894e-7 8.03424804528978e-11 0.0), #(-2.11572047798556e-7 -7.02123429895677e-11 0.0), #(-1.11656829528599e-5 3.29740544390964e-10 0.0), #(5.88498385990865e-5 2.54748780062977e-10 0.0) tevelocity:, 2, #(0.307842626631501 -1.05710206152388e-15 0.0), #(-0.306375565942897 4.39169137546245e-12 0.0), #(0.306191451559405 -5.2147365791715e-11 0.0), #(-0.302374230904649 5.21430531539878e-12 0.0), #(0.301861636273583 -7.89021001345105e-12 0.0), #(-0.295952089064426 -1.08606617225004e-10 0.0), #(0.2943892343767 -1.2497561620612e-11 0.0), #(-0.27378153579097 -2.61950834357133e-12 0.0), #(0.246972085727235 6.78484070946508e-12 0.0) tevelocity:, 3, #(0.307874225357897 2.98191519834776e-15 0.0), #(-0.30722391019847 8.68970169510119e-11 0.0), #(0.306812900930046 -1.84388853008345e-10 0.0), #(-0.305355084193399 -5.3571389939689e-12 0.0), #(0.304265426376774 4.91908787004334e-13 0.0), #(-0.301341960337996 -3.28548624382275e-11 0.0), #(0.298125554089018 -6.44688040255094e-12 0.0), #(-0.283177075609072 -4.84518748634126e-12 0.0), #(0.222551861651346 5.59117224725802e-12 0.0) and so on How do I calculate the group velocity of the guided mode? _______________________________________________ mpb-discuss mailing list mpb-discuss@ab-initio.mit.edu http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/mpb-discuss
