Optical constants

Refractive index of BaGa4Se7 (Barium gallium selenide, BGSe)

Badikov et al 2010: n(γ) 0.480–10.4 µm

Data
formula 4
Range
0.48–10.4 µm
Optical axis
gamma
Licence
CC0-1.0

Biaxial crystal, axes: gamma

Plot

Click the plot to set the calculator wavelength.

At one wavelength

Range 0.48–10.4 µm
Refractive index n
2.72517
Extinction coefficient k
0
Permittivity ε1
7.42656
Permittivity ε2
0
Absorption coefficient α
0 cm⁻¹
Penetration depth δ = λ/(2πk)
— nm
Abbe number Vd
9.041
Chromatic dispersion dn/dλ
-0.928402 µm⁻¹
Group index ng
3.2707
Group velocity dispersion
2163.18 fs²/mm
Dispersion parameter D
-11801.3 ps/(nm·km)
Photon energy
2.11001 eV

ε = (n + ik)², α = 4πk/λ, ng = 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

# BaGa4Se7 (Barium gallium selenide, BGSe): Badikov et al 2010: n(γ) 0.480–10.4 µm
baga4se7 = ls.fetch_refractiveindex("main", "BaGa4Se7", "Badikov-γ", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(baga4se7.range_nm)  # (480, 10400) nm
eps = baga4se7.eps([633])  # complex permittivity

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

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
n2=7.764197+0.326812λ0.0λ2−0.0697341.0+1975.857λ0.0λ2−1297.0791.0

Valid from 0.48 to 10.4 µm.

Coefficients as stored
CiValue
C17.764197
C20.326812
C30.0
C40.069734
C51.0
C61975.857
C70.0
C81297.079
C91.0

Comments and conditions

nγ; room temperature.

Conditions

direction
gamma

References

V. Badikov, D. Badikov, G. Shevyrdyaeva, A. Tyazhev, G. Marchev, V. Panyutin, V. Petrov, A. Kwasniewski. Phase-matching properties of BaGa4S7 and BaGa4Se7: Wide-bandgap nonlinear crystals for the mid-infrared. Phys. Status Solidi RRL, 5, 31–33 (2010)
  • doi:10.1002/pssr.201004425 Phase‐matching properties of BaGa<sub>4</sub>S<sub>7</sub> and BaGa<sub>4</sub>Se<sub>7</sub>: Wide‐bandgap nonlinear crystals for the mid‐infrared, physica status solidi (RRL) – Rapid Research Letters (2010)

Cite

Valeriy Badikov et al.. Phase‐matching properties of BaGa<sub>4</sub>S<sub>7</sub> and BaGa<sub>4</sub>Se<sub>7</sub>: Wide‐bandgap nonlinear crystals for the mid‐infrared. physica status solidi (RRL) – Rapid Research Letters, 5, 31-33 (2010), doi:10.1002/pssr.201004425; 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
BaGa4Se7 (Barium gallium selenide, BGSe), Badikov et al 2010: n(γ) 0.480–10.4 µm: n and k versus wavelength
λ (µm)n
0.482.876582
0.4837142.868865
0.4874582.861345
0.491232.854015
0.4950312.846869
0.4988622.839901
0.5027232.833105
0.5066132.826476
0.5105332.820007
0.5144842.813695
0.5184652.807533
0.5224772.801518
0.5265212.795645
0.5305952.78991
0.5347012.784307
0.5388392.778835
0.5430092.773487
0.5472112.768262
0.5514452.763155
0.5557132.758163
0.5600132.753282
0.5643472.74851
0.5687142.743844
0.5731152.73928
0.577552.734815
0.5820192.730448
0.5865232.726174
0.5910622.721993
0.5956362.7179
0.6002452.713895
0.604892.709974
0.6095712.706135
0.6142892.702377
0.6190422.698697
0.6238332.695093
0.628662.691563
0.6335252.688106
0.6384282.684719
0.6433682.681401
0.6483472.67815
0.6533642.674965
0.658422.671843
0.6635152.668784
0.668652.665785
0.6738242.662846
0.6790392.659964
0.6842932.65714
0.6895892.65437
0.6949252.651654
0.7003032.648991
0.7057222.64638
0.7111832.643819
0.7166872.641306
0.7222332.638842
0.7278222.636425
0.7334542.634054
0.739132.631727
0.744852.629444
0.7506142.627205
0.7564222.625007
0.7622762.62285
0.7681752.620733
0.7741192.618656
0.780112.616617
0.7861472.614615
0.792232.61265
0.7983612.610722
0.8045392.608828
0.8107652.606969
0.8170392.605144
0.8233622.603351
0.8297332.601592
0.8361542.599863
0.8426252.598166
0.8491462.5965
0.8557172.594863
0.8623392.593255
0.8690122.591676
0.8757372.590125
0.8825142.588601
0.8893432.587104
0.8962252.585634
0.903162.584189
0.910152.58277
0.9171932.581375
0.924292.580005
0.9314432.578658
0.9386512.577335
0.9459152.576035
0.9532352.574758
0.9606112.573502
0.9680452.572268
0.9755362.571056
0.9830852.569864
0.9906932.568692
0.998362.567541
1.006092.566409
1.013872.565296
1.021722.564202
1.029622.563127
1.037592.56207
1.045622.561031
1.053712.560009
1.061872.559005
1.070082.558017
1.078362.557046
1.086712.556091
1.095122.555152
1.103592.554229
1.112132.553321
1.120742.552428
1.129412.55155
1.138152.550687
1.146962.549838
1.155842.549002
1.164782.548181
1.173792.547373
1.182882.546578
1.192032.545797
1.201262.545028
1.210552.544272
1.219922.543528
1.229362.542796
1.238872.542076
1.248462.541367
1.258122.54067
1.267862.539985
1.277672.53931
1.287562.538647
1.297522.537994
1.307562.537351
1.317682.536719
1.327882.536097
1.338152.535485
1.348512.534883
1.358942.53429
1.369462.533707
1.380062.533133
1.390742.532568
1.40152.532012
1.412342.531464
1.423272.530926
1.434292.530396
1.445392.529874
1.456572.52936
1.467842.528855
1.47922.528357
1.490652.527867
1.502182.527385
1.513812.52691
1.525522.526443
1.537332.525983
1.549222.52553
1.561212.525084
1.573292.524645
1.585472.524212
1.597742.523786
1.61012.523367
1.622562.522954
1.635122.522548
1.647772.522147
1.660522.521753
1.673372.521365
1.686322.520982
1.699372.520606
1.712522.520235
1.725782.519869
1.739132.519509
1.752592.519154
1.766152.518805
1.779822.518461
1.793592.518122
1.807472.517788
1.821462.517459
1.835552.517134
1.849762.516815
1.864072.5165
1.87852.51619
1.893032.515884
1.907682.515582
1.922452.515285
1.937322.514992
1.952322.514704
1.967422.514419
1.982652.514139
1.997992.513862
2.013452.51359
2.029032.513321
2.044732.513056
2.060562.512795
2.07652.512537
2.092572.512283
2.108772.512032
2.125082.511785
2.141532.511541
2.15812.511301
2.17482.511064
2.191632.510829
2.208592.510598
2.225682.51037
2.242912.510146
2.260262.509924
2.277752.509705
2.295382.509488
2.313142.509275
2.331042.509064
2.349082.508856
2.367262.508651
2.385582.508448
2.404042.508247
2.422642.508049
2.441392.507854
2.460282.507661
2.479322.50747
2.498512.507282
2.517842.507095
2.537332.506911
2.556962.506729
2.576752.506549
2.596692.506372
2.616792.506196
2.637042.506022
2.657442.50585
2.678012.50568
2.698732.505512
2.719622.505345
2.740662.50518
2.761872.505017
2.783242.504856
2.804782.504696
2.826492.504538
2.848362.504382
2.87042.504226
2.892612.504073
2.9152.503921
2.937552.50377
2.960292.50362
2.98322.503472
3.006282.503325
3.029542.50318
3.052992.503035
3.076612.502892
3.100422.50275
3.124422.502609
3.148592.502469
3.172962.50233
3.197512.502192
3.222262.502055
3.247192.501919
3.272322.501784
3.297642.50165
3.323162.501516
3.348882.501384
3.374792.501252
3.400912.501121
3.427232.50099
3.453752.500861
3.480482.500732
3.507412.500603
3.534552.500475
3.56192.500348
3.589472.500221
3.617242.500094
3.645242.499968
3.673452.499843
3.701872.499718
3.730522.499593
3.759392.499468
3.788482.499344
3.81782.49922
3.847342.499096
3.877112.498973
3.907122.49885
3.937352.498726
3.967822.498603
3.998532.49848
4.029472.498357
4.060652.498234
4.092072.498111
4.123742.497988
4.155652.497865
4.187812.497742
4.220222.497618
4.252882.497495
4.285792.497371
4.318952.497247
4.352372.497123
4.386062.496998
4.422.496874
4.45422.496748
4.488672.496623
4.523412.496497
4.558412.49637
4.593692.496243
4.629232.496116
4.665062.495988
4.701162.495859
4.737542.49573
4.77422.4956
4.811142.495469
4.848372.495338
4.885892.495206
4.92372.495073
4.961812.49494
5.00022.494805
5.03892.49467
5.077892.494533
5.117192.494396
5.156782.494258
5.196692.494118
5.236912.493978
5.277432.493837
5.318272.493694
5.359432.49355
5.40092.493405
5.442692.493259
5.484812.493111
5.527262.492962
5.570032.492812
5.613132.49266
5.656572.492507
5.700342.492353
5.744462.492196
5.788912.492039
5.833712.491879
5.878852.491718
5.924342.491555
5.970192.491391
6.016392.491225
6.062952.491056
6.109872.490886
6.157152.490714
6.204792.49054
6.252812.490364
6.30122.490186
6.349962.490006
6.39912.489823
6.448622.489639
6.498522.489452
6.548812.489262
6.599492.489071
6.650562.488877
6.702022.48868
6.753892.488481
6.806152.488279
6.858822.488074
6.91192.487867
6.965392.487657
7.019292.487444
7.073612.487228
7.128342.487009
7.183512.486787
7.23912.486562
7.295122.486334
7.351572.486103
7.408462.485868
7.465792.48563
7.523562.485388
7.581792.485143
7.640462.484894
7.699582.484642
7.759172.484386
7.819212.484126
7.879722.483862
7.94072.483593
8.002152.483321
8.064072.483045
8.126472.482764
8.189362.48248
8.252732.48219
8.31662.481896
8.380962.481598
8.445812.481294
8.511172.480986
8.577032.480673
8.643412.480355
8.710292.480032
8.77772.479703
8.845622.47937
8.914082.47903
8.983062.478685
9.052572.478335
9.122632.477978
9.193222.477616
9.264362.477247
9.336062.476873
9.40832.476492
9.481112.476104
9.554482.47571
9.628422.475309
9.702932.474901
9.778012.474487
9.853682.474065
9.929932.473635
10.00682.473199
10.08422.472754
10.16222.472302
10.24092.471841
10.32012.471373
10.42.470896

Optical transmission calculator

Free-standing sample in vacuum, normal incidence
Method
Transmittance T
—
Reflectance R
—

Fresnel reflection calculator

Direction
Rp
—
Rs
—
R = (Rp+Rs)/2
—
Phase φp
—
Phase φs
—
Brewster angle θB
—
Critical angle θC
—