At one wavelength

Refractive index n: 3.04484
Extinction coefficient k: 2.93246

Permittivity ε₁: 0.671743
Permittivity ε₂: 17.8577

Absorption coefficient α: 627133 cm⁻¹
Penetration depth δ = λ/(2πk): 31.8912 nm

Abbe number V_d: —
Chromatic dispersion dn/dλ: 1.34787 µm⁻¹

Group index n_g: 2.25283
Group velocity dispersion: — fs²/mm

Dispersion parameter D: — ps/(nm·km)
Photon energy: 2.11001 eV

ε = (n + ik)², α = 4πk/λ, n_g = n − λ dn/dλ, GVD = λ³/(2πc²) d²n/dλ², D = −(λ/c) d²n/dλ². Group-velocity dispersion is given for formula data only.

Use it in Lightsmith

Load this data in Python, simulate in one more line

pip install lightsmith

import lightsmith as ls

# Ge (Germanium): Amotchkina et al, 2020: n,k 0.400–11.0 µm
ge = ls.fetch_refractiveindex("main", "Ge", "Amotchkina", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(ge.range_nm)  # (400, 11000) nm
eps = ge.eps([633])  # complex permittivity

Downloads the original record once (pinned to the imported snapshot) and caches it.

import json, urllib.request
import lightsmith as ls

url = "https://materials.lightsmith.dev/v1/datasets/ds_7edd3895c97a/lightsmith"
ge = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(ge.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (ge/amotchkina-2020).

# ... load ge as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=ge)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=400, stop_nm=1000, num=81),
)
res = ls.solve(sim)  # exact Mie for a sphere
print(res.q_ext)     # extinction efficiency at each wavelength

Same spec runs with DDA, FDTD, BEM or T-matrix: ls.compare(sim, ["mie", "dda"]).

Materials guide Open a sphere of it in Studio Quick start Ask the community

Lightsmith is open source (MIT): Mie, T-matrix, BEM, DDA, FDTD, RCWA, TMM, mode solvers and inverse design behind one spec, on CPU or GPU. GitHub.

References

T. Amotchkina, M. Trubetskov, D. Hahner, V. Pervak. Characterization of e-beam evaporated Ge, YbF₃, ZnS, and LaF₃ thin films for laser-oriented coatings. Appl. Opt. 59, A40-A47 (2020) (Data kindly provided by Tatiana Amotchkina [data] [description])

doi:10.1364/ao.59.000a40 Characterization of e-beam evaporated Ge, YbF 3 , ZnS, and LaF 3 thin films for laser-oriented coatings, Applied Optics (2019)

Cite

Tatiana Amotchkina, Michael Trubetskov, Daniel Hahner and Vladimir Pervak. Characterization of e-beam evaporated Ge, YbF 3 , ZnS, and LaF 3 thin films for laser-oriented coatings. Applied Optics, 59, A40 (2019), doi:10.1364/ao.59.000a40; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

628 rows as published

CSV comma separated TXT tab separated YAML n, k Full database record original YAML All quantities CSV JSON metadata

Ge (Germanium), Amotchkina et al, 2020: n,k 0.400–11.0 µm: n and k versus wavelength
λ (µm)	n	k
0.4	3.0	2.5194
0.40939	3.0	2.48531
0.41879	3.0	2.45739
0.42818	3.0	2.44187
0.43757	3.0	2.44144
0.44696	3.0	2.45499
0.45636	3.0	2.47903
0.46575	3.0	2.5099
0.47514	3.0	2.5454
0.48454	3.0	2.58601
0.49393	3.0	2.63387
0.50332	3.00001	2.68749
0.51271	3.00025	2.74385
0.52211	3.00107	2.79707
0.5315	3.00274	2.83995
0.54089	3.00549	2.86821
0.55029	3.00959	2.88399
0.55968	3.01525	2.89581
0.56907	3.02275	2.91049
0.57846	3.03252	2.92638
0.58786	3.04519	2.93263
0.59725	3.06138	2.91762
0.60664	3.0815	2.8787
0.61604	3.10606	2.82171
0.62543	3.13527	2.75666
0.63482	3.16943	2.6905
0.64421	3.20855	2.62702
0.65361	3.25229	2.5671
0.663	3.29996	2.50996
0.67239	3.35093	2.45428
0.68178	3.40442	2.39882
0.69118	3.45974	2.34282
0.70057	3.51638	2.28593
0.70996	3.57389	2.22785
0.71936	3.63181	2.16824
0.72875	3.68977	2.10704
0.73814	3.7474	2.04421
0.74753	3.80425	1.97962
0.75693	3.85982	1.91309
0.76632	3.91386	1.84481
0.77571	3.9662	1.77499
0.78511	4.01639	1.70373
0.7945	4.06442	1.63147
0.80389	4.11007	1.55845
0.81328	4.153	1.4849
0.82268	4.19324	1.41102
0.83207	4.23044	1.33702
0.84146	4.26445	1.26301
0.85086	4.2945	1.18875
0.86025	4.3185	1.11347
0.86964	4.33525	1.03617
0.87903	4.34281	0.95579
0.88843	4.34187	0.87262
0.89782	4.34027	0.79025
0.90721	4.34332	0.71148
0.9166	4.35094	0.6369
0.926	4.36077	0.56667
0.93539	4.36995	0.49987
0.94478	4.3771	0.4364
0.95418	4.38163	0.37639
0.96357	4.38358	0.32011
0.97296	4.38317	0.26782
0.98235	4.381	0.21981
0.99175	4.3779	0.17636
1.00114	4.37427	0.13775
1.01053	4.37023	0.10424
1.01993	4.36606	0.07611
1.02932	4.3618	0.05357
1.03871	4.35727	0.0367
1.0481	4.3525	0.02536
1.0575	4.34765	0.0186
1.06689	4.34279	0.0152
1.07628	4.33809	0.0131
1.08568	4.33378	0.0107
1.09507	4.33004	0.00834
1.10446	4.32688	0.00622
1.11385	4.32388	0.00429
1.12325	4.3206	0.00254
1.13264	4.31665	0.00094
1.14203	4.31222	0.00034
1.15143	4.30767	0.00016
1.16082	4.30313	0.00014
1.17021	4.29867	0.00011
1.1796	4.29413	0.00016
1.189	4.28971	0.00055
1.19839	4.28538	0.00119
1.20778	4.2812	0.00194
1.21717	4.27686	0.0025
1.22657	4.27259	0.00299
1.23596	4.26879	0.00349
1.24535	4.26574	0.00397
1.25475	4.26307	0.00439
1.26414	4.26063	0.0044
1.27353	4.25814	0.00415
1.28292	4.25561	0.00368
1.29232	4.2527	0.00298
1.30171	4.24977	0.00225
1.3111	4.24698	0.00146
1.3205	4.24445	0.00077
1.32989	4.24219	0.00016
1.33928	4.24014	0.00048
1.34867	4.23817	0.00115
1.35807	4.23546	0.00165
1.36746	4.23267	0.00211
1.37685	4.22964	0.00218
1.38625	4.22672	0.00211
1.39564	4.22435	0.00127
1.40503	4.22225	0.00055
1.41442	4.22122	0.00034
1.42382	4.22029	0.00017
1.43321	4.2198	0.00018
1.4426	4.21932	0.00019
1.452	4.21886	0.00017
1.46139	4.21841	0.00015
1.47078	4.21824	0.00017
1.48017	4.21808	0.00019
1.48957	4.21761	0.00086
1.49896	4.21708	0.00167
1.50835	4.21678	0.0019
1.51774	4.21663	0.00172
1.52714	4.21661	0.00143
1.53653	4.21695	0.00085
1.54592	4.21729	0.00027
1.55532	4.21488	0.00027
1.56471	4.21218	0.00033
1.5741	4.20747	0.00051
1.58349	4.20038	0.00083
1.59289	4.19328	0.00114
1.60228	4.18694	0.00196
1.61167	4.18065	0.00281
1.62107	4.17514	0.00384
1.63046	4.17116	0.00521
1.63985	4.16717	0.00658
1.64924	4.16397	0.00773
1.65864	4.16115	0.00878
1.66803	4.15833	0.00983
1.67742	4.15592	0.00988
1.68682	4.15356	0.00983
1.69621	4.15122	0.0096
1.7056	4.14921	0.00632
1.71499	4.1472	0.00305
1.72439	4.14517	0.00016
1.73378	4.143	0.00019
1.74317	4.14083	0.00022
1.75256	4.13868	0.00024
1.76196	4.13684	0.0002
1.77135	4.135	0.00016
1.78074	4.13317	0.00012
1.79014	4.13221	0.0001
1.79953	4.13132	9e-05
1.80892	4.13043	7e-05
1.81831	4.12729	6e-05
1.82771	4.12313	5e-05
1.8371	4.11896	4e-05
1.84649	4.11333	4e-05
1.85589	4.10459	3e-05
1.86528	4.09586	3e-05
1.87467	4.08712	2e-05
1.88406	4.08027	2e-05
1.89346	4.07378	1e-05
1.90285	4.0673	1e-05
1.91224	4.06144	1e-05
1.92164	4.05768	1e-05
1.93103	4.05391	1e-05
1.94042	4.05015	0.0
1.94981	4.04669	0.0
1.95921	4.04353	0.0
1.9686	4.04037	0.0
1.97799	4.03722	0.0
1.98739	4.03876	0.0
1.99678	4.04333	0.0
2.00617	4.0479	0.0
2.01556	4.05247	0.0
2.02496	4.05287	0.0
2.03435	4.05025	0.0
2.04374	4.04763	0.0
2.05313	4.04502	0.0
2.06253	4.04299	0.0
2.07192	4.04188	0.0
2.08131	4.04077	0.0
2.09071	4.03967	0.0
2.1	4.0507	0.0
2.1001	4.03857	0.0
2.12	4.04891	0.0
2.14	4.04717	0.0
2.16	4.04548	0.0
2.18	4.04383	0.0
2.2	4.04224	0.0
2.22	4.04068	0.0
2.24	4.03916	0.0
2.26	4.03769	0.0
2.28	4.03625	0.0
2.3	4.03485	0.0
2.32	4.03349	0.0
2.34	4.03216	0.0
2.36	4.03087	0.0
2.38	4.02961	0.0
2.4	4.02838	0.0
2.42	4.02718	0.0
2.44	4.02601	0.0
2.46	4.02486	0.0
2.48	4.02375	0.0
2.5	4.02266	0.0
2.52	4.0216	0.0
2.54	4.02056	0.0
2.56	4.01955	0.0
2.58	4.01856	0.0
2.6	4.01759	0.0
2.62	4.01665	0.0
2.64	4.01572	0.0
2.66	4.01482	0.0
2.68	4.01394	0.0
2.7	4.01307	0.0
2.72	4.01223	0.0
2.74	4.0114	0.0
2.76	4.0106	0.0
2.78	4.00981	0.0
2.8	4.00903	0.0
2.82	4.00828	0.0
2.84	4.00753	0.0
2.86	4.00681	0.0
2.88	4.0061	0.0
2.9	4.0054	0.0
2.92	4.00472	0.0
2.94	4.00405	0.0
2.96	4.0034	0.0
2.98	4.00276	0.0
3.0	4.00213	0.0
3.02	4.00151	0.0
3.04	4.00091	0.0
3.06	4.00032	0.0
3.08	3.99974	0.0
3.1	3.99917	0.0
3.12	3.99861	0.0
3.14	3.99806	0.0
3.16	3.99752	0.0
3.18	3.997	0.0
3.2	3.99648	0.0
3.22	3.99597	0.0
3.24	3.99547	0.0
3.26	3.99498	0.0
3.28	3.9945	0.0
3.3	3.99403	0.0
3.32	3.99357	0.0
3.34	3.99311	0.0
3.36	3.99267	0.0
3.38	3.99223	0.0
3.4	3.9918	0.0
3.42	3.99137	0.0
3.44	3.99096	0.0
3.46	3.99055	0.0
3.48	3.99014	0.0
3.5	3.98975	0.0
3.52	3.98936	0.0
3.54	3.98898	0.0
3.56	3.9886	0.0
3.58	3.98823	0.0
3.6	3.98787	0.0
3.62	3.98751	0.0
3.64	3.98716	0.0
3.66	3.98682	0.0
3.68	3.98648	0.0
3.7	3.98614	0.0
3.72	3.98581	0.0
3.74	3.98549	0.0
3.76	3.98517	0.0
3.78	3.98486	0.0
3.8	3.98455	0.0
3.82	3.98425	0.0
3.84	3.98395	0.0
3.86	3.98365	0.0
3.88	3.98336	0.0
3.9	3.98308	0.0
3.92	3.9828	0.0
3.94	3.98252	0.0
3.96	3.98225	0.0
3.98	3.98198	0.0
4.0	3.98171	0.0
4.02	3.98145	0.0
4.04	3.9812	0.0
4.06	3.98094	0.0
4.08	3.9807	0.0
4.1	3.98045	0.0
4.12	3.98021	0.0
4.14	3.97997	0.0
4.16	3.97973	0.0
4.18	3.9795	0.0
4.2	3.97927	0.0
4.22	3.97905	0.0
4.24	3.97883	0.0
4.26	3.97861	0.0
4.28	3.97839	0.0
4.3	3.97818	0.0
4.32	3.97797	0.0
4.34	3.97776	0.0
4.36	3.97756	0.0
4.38	3.97736	0.0
4.4	3.97716	0.0
4.42	3.97696	0.0
4.44	3.97677	0.0
4.46	3.97658	0.0
4.48	3.97639	0.0
4.5	3.97621	0.0
4.52	3.97602	0.0
4.54	3.97584	0.0
4.56	3.97566	0.0
4.58	3.97549	0.0
4.6	3.97531	0.0
4.62	3.97514	0.0
4.64	3.97497	0.0
4.66	3.97481	0.0
4.68	3.97464	0.0
4.7	3.97448	0.0
4.72	3.97432	0.0
4.74	3.97416	0.0
4.76	3.974	0.0
4.78	3.97385	0.0
4.8	3.97369	0.0
4.82	3.97354	0.0
4.84	3.97339	0.0
4.86	3.97325	0.0
4.88	3.9731	0.0
4.9	3.97296	0.0
4.92	3.97282	0.0
4.94	3.97268	0.0
4.96	3.97254	0.0
4.98	3.9724	0.0
5.0	3.97227	0.0
5.02	3.97213	0.0
5.04	3.972	0.0
5.06	3.97187	0.0
5.08	3.97174	0.0
5.1	3.97161	0.0
5.12	3.97149	0.0
5.14	3.97136	0.0
5.16	3.97124	0.0
5.18	3.97112	0.0
5.2	3.971	0.0
5.22	3.97088	0.0
5.24	3.97076	0.0
5.26	3.97065	0.0
5.28	3.97053	0.0
5.3	3.97042	0.0
5.32	3.97031	0.0
5.34	3.97019	0.0
5.36	3.97008	0.0
5.38	3.96998	0.0
5.4	3.96987	0.0
5.42	3.96976	0.0
5.44	3.96966	0.0
5.46	3.96955	0.0
5.48	3.96945	0.0
5.5	3.96935	0.0
5.52	3.96925	0.0
5.54	3.96915	0.0
5.56	3.96905	0.0
5.58	3.96895	0.0
5.6	3.96886	0.0
5.62	3.96876	0.0
5.64	3.96867	0.0
5.66	3.96858	0.0
5.68	3.96848	0.0
5.7	3.96839	0.0
5.72	3.9683	0.0
5.74	3.96821	0.0
5.76	3.96812	0.0
5.78	3.96804	0.0
5.8	3.96795	0.0
5.82	3.96787	0.0
5.84	3.96778	0.0
5.86	3.9677	0.0
5.88	3.96761	0.0
5.9	3.96753	0.0
5.92	3.96745	0.0
5.94	3.96737	0.0
5.96	3.96729	0.0
5.98	3.96721	0.0
6.0	3.96713	0.0
6.02	3.96705	0.0
6.04	3.96698	0.0
6.06	3.9669	0.0
6.08	3.96683	0.0
6.1	3.96675	0.0
6.12	3.96668	0.0
6.14	3.96661	0.0
6.16	3.96653	0.0
6.18	3.96646	0.0
6.2	3.96639	0.0
6.22	3.96632	0.0
6.24	3.96625	0.0
6.26	3.96618	0.0
6.28	3.96612	0.0
6.3	3.96605	0.0
6.32	3.96598	0.0
6.34	3.96591	0.0
6.36	3.96585	0.0
6.38	3.96578	0.0
6.4	3.96572	0.0
6.42	3.96566	0.0
6.44	3.96559	0.0
6.46	3.96553	0.0
6.48	3.96547	0.0
6.5	3.96541	0.0
6.52	3.96535	0.0
6.54	3.96529	0.0
6.56	3.96523	0.0
6.58	3.96517	0.0
6.6	3.96511	0.0
6.62	3.96505	0.0
6.64	3.96499	0.0
6.66	3.96493	0.0
6.68	3.96488	0.0
6.7	3.96482	0.0
6.72	3.96477	0.0
6.74	3.96471	0.0
6.76	3.96466	0.0
6.78	3.9646	0.0
6.8	3.96455	0.0
6.82	3.9645	0.0
6.84	3.96444	0.0
6.86	3.96439	0.0
6.88	3.96434	0.0
6.9	3.96429	0.0
6.92	3.96424	0.0
6.94	3.96419	0.0
6.96	3.96414	0.0
6.98	3.96409	0.0
7.0	3.96404	0.0
7.02	3.96399	0.0
7.04	3.96394	0.0
7.06	3.96389	0.0
7.08	3.96384	0.0
7.1	3.9638	0.0
7.12	3.96375	0.0
7.14	3.9637	0.0
7.16	3.96366	0.0
7.18	3.96361	0.0
7.2	3.96357	0.0
7.22	3.96352	0.0
7.24	3.96348	0.0
7.26	3.96343	0.0
7.28	3.96339	0.0
7.3	3.96335	0.0
7.32	3.9633	0.0
7.34	3.96326	0.0
7.36	3.96322	0.0
7.38	3.96318	0.0
7.4	3.96314	0.0
7.42	3.96309	0.0
7.44	3.96305	0.0
7.46	3.96301	0.0
7.48	3.96297	0.0
7.5	3.96293	0.0
7.52	3.96289	0.0
7.54	3.96285	0.0
7.56	3.96281	0.0
7.58	3.96278	0.0
7.6	3.96274	0.0
7.62	3.9627	0.0
7.64	3.96266	0.0
7.66	3.96262	0.0
7.68	3.96259	0.0
7.7	3.96255	0.0
7.72	3.96251	0.0
7.74	3.96248	0.0
7.76	3.96244	0.0
7.78	3.96241	0.0
7.8	3.96237	0.0
7.82	3.96233	0.0
7.84	3.9623	0.0
7.86	3.96226	0.0
7.88	3.96223	0.0
7.9	3.9622	0.0
7.92	3.96216	0.0
7.94	3.96213	0.0
7.96	3.96209	0.0
7.98	3.96206	0.0
8.0	3.96203	0.0
8.02	3.962	0.0
8.04	3.96196	0.0
8.06	3.96193	0.0
8.08	3.9619	0.0
8.1	3.96187	0.0
8.12	3.96184	0.0
8.14	3.9618	0.0
8.16	3.96177	0.0
8.18	3.96174	0.0
8.2	3.96171	0.0
8.22	3.96168	0.0
8.24	3.96165	0.0
8.26	3.96162	0.0
8.28	3.96159	0.0
8.3	3.96156	0.0
8.32	3.96153	0.0
8.34	3.9615	0.0
8.36	3.96148	0.0
8.38	3.96145	0.0
8.4	3.96142	0.0
8.42	3.96139	0.0
8.44	3.96136	0.0
8.46	3.96133	0.0
8.48	3.96131	0.0
8.5	3.96128	0.0
8.52	3.96125	0.0
8.54	3.96123	0.0
8.56	3.9612	0.0
8.58	3.96117	0.0
8.6	3.96115	0.0
8.62	3.96112	0.0
8.64	3.96109	0.0
8.66	3.96107	0.0
8.68	3.96104	0.0
8.7	3.96102	0.0
8.72	3.96099	0.0
8.74	3.96096	0.0
8.76	3.96094	0.0
8.78	3.96091	0.0
8.8	3.96089	0.0
8.82	3.96087	0.0
8.84	3.96084	0.0
8.86	3.96082	0.0
8.88	3.96079	0.0
8.9	3.96077	0.0
8.92	3.96074	0.0
8.94	3.96072	0.0
8.96	3.9607	0.0
8.98	3.96067	0.0
9.0	3.96065	0.0
9.02	3.96063	0.0
9.04	3.96061	0.0
9.06	3.96058	0.0
9.08	3.96056	0.0
9.1	3.96054	0.0
9.12	3.96052	0.0
9.14	3.96049	0.0
9.16	3.96047	0.0
9.18	3.96045	0.0
9.2	3.96043	0.0
9.22	3.96041	0.0
9.24	3.96039	0.0
9.26	3.96036	0.0
9.28	3.96034	0.0
9.3	3.96032	0.0
9.32	3.9603	0.0
9.34	3.96028	0.0
9.36	3.96026	0.0
9.38	3.96024	0.0
9.4	3.96022	0.0
9.42	3.9602	0.0
9.44	3.96018	0.0
9.46	3.96016	0.0
9.48	3.96014	0.0
9.5	3.96012	0.0
9.52	3.9601	0.0
9.54	3.96008	0.0
9.56	3.96006	0.0
9.58	3.96004	0.0
9.6	3.96002	0.0
9.62	3.96	0.0
9.64	3.95999	0.0
9.66	3.95997	0.0
9.68	3.95995	0.0
9.7	3.95993	0.0
9.72	3.95991	0.0
9.74	3.95989	0.0
9.76	3.95988	0.0
9.78	3.95986	0.0
9.8	3.95984	0.0
9.82	3.95982	0.0
9.84	3.9598	0.0
9.86	3.95979	0.0
9.88	3.95977	0.0
9.9	3.95975	0.0
9.92	3.95973	0.0
9.94	3.95972	0.0
9.96	3.9597	0.0
9.98	3.95968	0.0
10.0	3.95967	0.0
10.02	3.95965	0.0
10.04	3.95963	0.0
10.06	3.95962	0.0
10.08	3.9596	0.0
10.1	3.95958	0.0
10.12	3.95957	0.0
10.14	3.95955	0.0
10.16	3.95954	0.0
10.18	3.95952	0.0
10.2	3.9595	0.0
10.22	3.95949	0.0
10.24	3.95947	0.0
10.26	3.95946	0.0
10.28	3.95944	0.0
10.3	3.95943	0.0
10.32	3.95941	0.0
10.34	3.95939	0.0
10.36	3.95938	0.0
10.38	3.95936	0.0
10.4	3.95935	0.0
10.42	3.95933	0.0
10.44	3.95932	0.0
10.46	3.95931	0.0
10.48	3.95929	0.0
10.5	3.95928	0.0
10.52	3.95926	0.0
10.54	3.95925	0.0
10.56	3.95923	0.0
10.58	3.95922	0.0
10.6	3.9592	0.0
10.62	3.95919	0.0
10.64	3.95918	0.0
10.66	3.95916	0.0
10.68	3.95915	0.0
10.7	3.95913	0.0
10.72	3.95912	0.0
10.74	3.95911	0.0
10.76	3.95909	0.0
10.78	3.95908	0.0
10.8	3.95907	0.0
10.82	3.95905	0.0
10.84	3.95904	0.0
10.86	3.95903	0.0
10.88	3.95901	0.0
10.9	3.959	0.0
10.92	3.95899	0.0
10.94	3.95898	0.0
10.96	3.95896	0.0
10.98	3.95895	0.0
11.0	3.95894	0.0

Optical transmission calculator

Free-standing sample in vacuum, normal incidence

Transmittance T: —
Reflectance R: —

Fresnel reflection calculator

R_p: —
R_s: —
R = (R_p+R_s)/2: —
Phase φ_p: —
Phase φ_s: —
Brewster angle θ_B: —
Critical angle θ_C: —

Plot