wavelength, nm - waveguide  width 400		420		430		440		450 nm
1250	-2.095	1250	-2.0744	1250	-2.0642	1250	-2.0544	1250	-2.044	
1275	-2.0518	1275	-2.0358	1275	-2.0276	1275	-2.0194	1275	-2.0108	
1300	-2.0086	1300	-1.9972	1300	-1.991	1300	-1.9844	1300	-1.9776	
1325	-1.9546	1325	-1.9484	1325	-1.9446	1325	-1.94	1325	-1.9352	
1350	-1.8906	1350	-1.8904	1350	-1.889	1350	-1.887	1350	-1.8842	
1375	-1.819	1375	-1.825	1375	-1.8262	1375	-1.8268	1375	-1.8266	
1400	-1.7372	1400	-1.7494	1400	-1.7538	1400	-1.757	1400	-1.7594	
1425	-1.6444	1425	-1.6632	1425	-1.6704	1425	-1.6764	1425	-1.6814	
1450	-1.546	1450	-1.5708	1450	-1.5806	1450	-1.5894	1450	-1.5968	
1475	-1.4426	1475	-1.4724	1475	-1.4848	1475	-1.496	1475	-1.5058	
1500	-1.337	1500	-1.3712	1500	-1.386	1500	-1.3994	1500	-1.4116	
1525	-1.2308	1525	-1.2686	1525	-1.2854	1525	-1.3004	1525	-1.3142	
1550	-1.1252	1550	-1.1654	1550	-1.1832	1550	-1.1996	1550	-1.2148	
1575	-1.024	1575	-1.0654	1575	-1.084	1575	-1.1016	1575	-1.1178	
1600	-0.9274	1600	-0.9694	1600	-0.9886	1600	-1.0066	1600	-1.0234	
1625	-0.837	1625	-0.8786	1625	-0.8978	1625	-0.9158	1625	-0.933	
1650	-0.7466	1650	-0.7878	1650	-0.807	1650	-0.825	1650	-0.8426