Optical constants

Refractive index of BaGa₂GeSe₆ (BGGSe)

Kato et al. 2018: n(e) 0.778–10.6 µm

Data: formula 4
Range: 0.778–10.6 µm
Optical axis: e
Licence: CC0-1.0

Uniaxial crystal, axes: oe

Axis Log x Log y

Click the plot to set the calculator wavelength.

At one wavelength

Refractive index n: 2.56613
Extinction coefficient k: 0

Permittivity ε₁: 6.58503
Permittivity ε₂: 0

Absorption coefficient α: 0 cm⁻¹
Penetration depth δ = λ/(2πk): — nm

Abbe number V_d: —
Chromatic dispersion dn/dλ: -0.00640937 µm⁻¹

Group index n_g: 2.58453
Group velocity dispersion: 211.172 fs²/mm

Dispersion parameter D: -48.2917 ps/(nm·km)
Photon energy: 0.432001 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

# BaGa2GeSe6 (BGGSe): Kato et al. 2018: n(e) 0.778–10.6 µm
baga2gese6 = ls.fetch_refractiveindex("main", "BaGa2GeSe6", "Kato-e", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(baga2gese6.range_nm)  # (778, 10600) nm
eps = baga2gese6.eps([2870])  # 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_fc1dcd517876/lightsmith"
baga2gese6 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(baga2gese6.source)  # citation and provenance travel with the data

Any dataset here, as the library's Tabulated material (baga2gese6/kato-2018-e).

# ... load baga2gese6 as above, then:
sim = ls.Simulation(
    particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=baga2gese6)],
    medium_index=1.0,
    wavelengths=ls.WavelengthRange(start_nm=778, 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.

Dispersion formula

RefractiveIndex.INFO (formula 4), λ in µm

n^{2} = 8.11658 + \frac{0.30287 λ^{0.0}}{λ^{2} - {0.13199}^{1.0}} + \frac{2197.51 λ^{0.0}}{λ^{2} - {1408.89}^{1.0}}

Valid from 0.778 to 10.6 µm.

Coefficients as stored

C_i	Value
C1	8.11658
C2	0.30287
C3	0.0
C4	0.13199
C5	1.0
C6	2197.51
C7	0.0
C8	1408.89
C9	1.0

Comments and conditions

Extraordinary ray (e); room temperature.

Conditions

direction: e

References

K. Kato, K. Miyata, V. V. Badikov, V. Petrov. Phase-matching properties of BaGa₂GeSe₆ for three-wave interactions in the 0.778–10.5910 μm spectral range. Appl. Opt., 57, 7440–7443 (2018)

doi:10.1364/ao.57.007440 Phase-matching properties of BaGa2GeSe6 for three-wave interactions in the 0778–105910 μm spectral range, Applied Optics (2018)

Cite

Kiyoshi Kato, Kentaro Miyata, Valeriy V. Badikov and Valentin Petrov. Phase-matching properties of BaGa2GeSe6 for three-wave interactions in the 0778–105910 μm spectral range. Applied Optics, 57, 7440 (2018), doi:10.1364/ao.57.007440; Data from the refractiveindex.info database (M. N. Polyanskiy, Sci. Data 11, 94 (2024), doi:10.1038/s41597-023-02898-2)

Data

Computed on 400 wavelengths, the same grid as the API and the library

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

BaGa2GeSe6 (BGGSe), Kato et al. 2018: n(e) 0.778–10.6 µm: n and k versus wavelength
λ (µm)	n
0.778	2.682552
0.78311	2.680572
0.788253	2.678631
0.79343	2.676728
0.79864	2.67486
0.803886	2.673029
0.809165	2.671232
0.814479	2.669468
0.819828	2.667738
0.825213	2.66604
0.830632	2.664374
0.836088	2.662738
0.841579	2.661132
0.847106	2.659556
0.852669	2.658008
0.858269	2.656489
0.863906	2.654996
0.869579	2.653531
0.87529	2.652092
0.881039	2.650678
0.886825	2.64929
0.89265	2.647926
0.898512	2.646585
0.904413	2.645269
0.910353	2.643975
0.916332	2.642704
0.92235	2.641455
0.928407	2.640227
0.934505	2.63902
0.940642	2.637834
0.94682	2.636668
0.953038	2.635522
0.959297	2.634396
0.965597	2.633288
0.971939	2.632199
0.978322	2.631128
0.984747	2.630075
0.991215	2.629039
0.997725	2.628021
1.00428	2.627019
1.01087	2.626034
1.01751	2.625065
1.02419	2.624112
1.03092	2.623174
1.03769	2.622251
1.04451	2.621344
1.05137	2.620451
1.05827	2.619572
1.06522	2.618708
1.07222	2.617857
1.07926	2.61702
1.08635	2.616196
1.09348	2.615385
1.10066	2.614587
1.10789	2.613801
1.11517	2.613028
1.12249	2.612267
1.12986	2.611518
1.13728	2.610781
1.14475	2.610055
1.15227	2.60934
1.15984	2.608636
1.16746	2.607943
1.17512	2.607261
1.18284	2.606589
1.19061	2.605927
1.19843	2.605276
1.2063	2.604634
1.21422	2.604002
1.2222	2.60338
1.23022	2.602767
1.2383	2.602163
1.24644	2.601569
1.25462	2.600983
1.26286	2.600406
1.27116	2.599837
1.2795	2.599277
1.28791	2.598726
1.29637	2.598182
1.30488	2.597647
1.31345	2.597119
1.32208	2.596599
1.33076	2.596087
1.3395	2.595583
1.3483	2.595085
1.35715	2.594595
1.36606	2.594112
1.37504	2.593636
1.38407	2.593167
1.39316	2.592704
1.40231	2.592249
1.41152	2.5918
1.42079	2.591357
1.43012	2.59092
1.43951	2.59049
1.44896	2.590066
1.45848	2.589648
1.46806	2.589236
1.4777	2.58883
1.4874	2.588429
1.49717	2.588034
1.50701	2.587645
1.5169	2.587261
1.52687	2.586882
1.53689	2.586509
1.54699	2.586141
1.55715	2.585778
1.56737	2.58542
1.57767	2.585067
1.58803	2.584718
1.59846	2.584375
1.60896	2.584036
1.61952	2.583702
1.63016	2.583373
1.64086	2.583048
1.65164	2.582727
1.66249	2.582411
1.67341	2.582099
1.6844	2.581791
1.69546	2.581487
1.70659	2.581188
1.7178	2.580892
1.72908	2.580601
1.74044	2.580313
1.75187	2.580029
1.76338	2.579749
1.77496	2.579472
1.78661	2.579199
1.79835	2.57893
1.81016	2.578664
1.82205	2.578402
1.83401	2.578143
1.84606	2.577888
1.85818	2.577636
1.87039	2.577387
1.88267	2.577141
1.89503	2.576898
1.90748	2.576659
1.92001	2.576422
1.93262	2.576189
1.94531	2.575958
1.95809	2.575731
1.97095	2.575506
1.98389	2.575284
1.99692	2.575065
2.01003	2.574848
2.02324	2.574635
2.03652	2.574423
2.0499	2.574215
2.06336	2.574009
2.07691	2.573805
2.09055	2.573604
2.10428	2.573406
2.1181	2.57321
2.13201	2.573016
2.14601	2.572824
2.16011	2.572635
2.1743	2.572448
2.18857	2.572263
2.20295	2.57208
2.21742	2.5719
2.23198	2.571721
2.24664	2.571545
2.26139	2.571371
2.27624	2.571198
2.29119	2.571028
2.30624	2.570859
2.32139	2.570693
2.33663	2.570528
2.35198	2.570365
2.36743	2.570204
2.38297	2.570044
2.39862	2.569887
2.41438	2.569731
2.43023	2.569576
2.4462	2.569424
2.46226	2.569273
2.47843	2.569123
2.49471	2.568975
2.51109	2.568829
2.52758	2.568684
2.54418	2.56854
2.56089	2.568398
2.57771	2.568258
2.59464	2.568119
2.61168	2.567981
2.62883	2.567844
2.6461	2.567709
2.66348	2.567575
2.68097	2.567443
2.69858	2.567311
2.7163	2.567181
2.73414	2.567052
2.7521	2.566924
2.77017	2.566798
2.78836	2.566672
2.80668	2.566548
2.82511	2.566424
2.84366	2.566302
2.86234	2.566181
2.88114	2.56606
2.90006	2.565941
2.91911	2.565823
2.93828	2.565705
2.95758	2.565589
2.977	2.565473
2.99655	2.565358
3.01623	2.565244
3.03604	2.565131
3.05598	2.565019
3.07605	2.564907
3.09625	2.564797
3.11659	2.564687
3.13706	2.564577
3.15766	2.564469
3.1784	2.564361
3.19927	2.564254
3.22028	2.564147
3.24143	2.564041
3.26272	2.563936
3.28415	2.563831
3.30572	2.563727
3.32743	2.563623
3.34928	2.56352
3.37128	2.563418
3.39342	2.563316
3.4157	2.563214
3.43814	2.563113
3.46072	2.563012
3.48345	2.562912
3.50632	2.562812
3.52935	2.562713
3.55253	2.562614
3.57586	2.562515
3.59935	2.562416
3.62298	2.562318
3.64678	2.56222
3.67073	2.562123
3.69484	2.562026
3.7191	2.561928
3.74353	2.561832
3.76811	2.561735
3.79286	2.561639
3.81777	2.561542
3.84284	2.561446
3.86808	2.56135
3.89349	2.561254
3.91906	2.561159
3.9448	2.561063
3.9707	2.560967
3.99678	2.560872
4.02303	2.560776
4.04945	2.560681
4.07605	2.560585
4.10282	2.56049
4.12976	2.560394
4.15688	2.560299
4.18418	2.560203
4.21166	2.560107
4.23932	2.560011
4.26717	2.559915
4.29519	2.559819
4.3234	2.559723
4.35179	2.559626
4.38037	2.55953
4.40914	2.559433
4.4381	2.559336
4.46725	2.559238
4.49659	2.559141
4.52612	2.559043
4.55584	2.558945
4.58576	2.558846
4.61588	2.558747
4.6462	2.558648
4.67671	2.558549
4.70743	2.558449
4.73834	2.558348
4.76946	2.558247
4.80078	2.558146
4.83231	2.558044
4.86405	2.557942
4.89599	2.557839
4.92815	2.557736
4.96052	2.557632
4.99309	2.557528
5.02589	2.557423
5.05889	2.557318
5.09212	2.557211
5.12556	2.557105
5.15922	2.556997
5.19311	2.556889
5.22721	2.55678
5.26154	2.556671
5.2961	2.55656
5.33088	2.556449
5.36589	2.556337
5.40113	2.556225
5.4366	2.556111
5.47231	2.555997
5.50825	2.555882
5.54442	2.555766
5.58084	2.555649
5.61749	2.555531
5.65438	2.555412
5.69152	2.555292
5.7289	2.555171
5.76652	2.555049
5.80439	2.554926
5.84252	2.554802
5.88089	2.554677
5.91951	2.554551
5.95839	2.554423
5.99752	2.554294
6.03691	2.554165
6.07655	2.554034
6.11646	2.553901
6.15663	2.553768
6.19707	2.553633
6.23777	2.553497
6.27873	2.553359
6.31997	2.55322
6.36148	2.55308
6.40325	2.552938
6.44531	2.552795
6.48764	2.55265
6.53025	2.552504
6.57313	2.552356
6.6163	2.552206
6.65976	2.552055
6.70349	2.551903
6.74752	2.551748
6.79183	2.551592
6.83644	2.551434
6.88134	2.551275
6.92653	2.551113
6.97202	2.55095
7.01781	2.550785
7.0639	2.550618
7.11029	2.550449
7.15699	2.550278
7.204	2.550105
7.25131	2.54993
7.29893	2.549752
7.34687	2.549573
7.39512	2.549392
7.44369	2.549208
7.49257	2.549022
7.54178	2.548834
7.59131	2.548643
7.64117	2.54845
7.69135	2.548255
7.74186	2.548057
7.79271	2.547857
7.84389	2.547654
7.8954	2.547449
7.94726	2.547241
7.99945	2.54703
8.05199	2.546817
8.10487	2.546601
8.1581	2.546382
8.21168	2.54616
8.26561	2.545935
8.31989	2.545707
8.37453	2.545477
8.42953	2.545243
8.4849	2.545006
8.54062	2.544766
8.59671	2.544522
8.65317	2.544276
8.71	2.544026
8.7672	2.543772
8.82478	2.543515
8.88274	2.543255
8.94108	2.542991
8.9998	2.542723
9.05891	2.542452
9.1184	2.542177
9.17829	2.541898
9.23856	2.541615
9.29924	2.541328
9.36031	2.541037
9.42179	2.540742
9.48366	2.540442
9.54595	2.540139
9.60864	2.539831
9.67175	2.539518
9.73527	2.539201
9.7992	2.53888
9.86356	2.538554
9.92834	2.538223
9.99354	2.537887
10.0592	2.537546
10.1252	2.537201
10.1917	2.53685
10.2587	2.536494
10.326	2.536133
10.3939	2.535766
10.4621	2.535394
10.5308	2.535016
10.6	2.534633

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: —

BaGa₂GeSe₆ (BGGSe): all datasets

About BaGa2GeSe6 (BGGSe)

BaGa₂GeSe₆ (BGGSe) is a nonlinear optical crystal known for its wide transparency range and phase-matching capabilities in the mid-infrared region. It is particularly effective for frequency conversion applications, such as optical parametric oscillation, due to its high nonlinear optical coefficients. The material's broad phase-matching range and wide transparency window make it ideal for tunable laser systems operating in the mid-infrared spectrum. BGGSe also exhibits a high laser damage threshold, which makes it suitable for high-power applications. However, like many other chalcogenide crystals, it can be sensitive to moisture and requires careful handling and storage to maintain its optical quality. The crystal is typically grown using the Bridgman technique and can be polished into high-quality facets for optimal performance. Overall, BaGa₂GeSe₆ (BGGSe) represents a compelling option for nonlinear optical applications requiring a broad tunability and high power-handling capacity in the mid-infrared region.

More about BaGa2GeSe6 (BGGSe) →

Provenance

Version: 1 (snapshot c5c2f18)
Source page: refractiveindex.info
Original file: database/data/main/BaGa2GeSe6/nk/Kato-e.yml
ID: ds_fc1dcd517876
API: /v1/datasets/ds_fc1dcd517876

Plot