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
- 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.
import json, urllib.request
import lightsmith as ls
url = "https://materials.lightsmith.dev/v1/datasets/ds_17d81dce2d06/lightsmith"
baga4se7 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(baga4se7.source) # citation and provenance travel with the data
Any dataset here, as the library's Tabulated material (baga4se7/badikov-2010-3).
# ... load baga4se7 as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=baga4se7)],
medium_index=1.0,
wavelengths=ls.WavelengthRange(start_nm=480, 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"]).
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 µmValid from 0.48 to 10.4 µm.
Coefficients as stored
| Ci | Value |
|---|---|
| C1 | 7.764197 |
| C2 | 0.326812 |
| C3 | 0.0 |
| C4 | 0.069734 |
| C5 | 1.0 |
| C6 | 1975.857 |
| C7 | 0.0 |
| C8 | 1297.079 |
| C9 | 1.0 |
Comments and conditions
Conditions
- direction
- gamma
References
- 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| λ (µm) | n |
|---|---|
| 0.48 | 2.876582 |
| 0.483714 | 2.868865 |
| 0.487458 | 2.861345 |
| 0.49123 | 2.854015 |
| 0.495031 | 2.846869 |
| 0.498862 | 2.839901 |
| 0.502723 | 2.833105 |
| 0.506613 | 2.826476 |
| 0.510533 | 2.820007 |
| 0.514484 | 2.813695 |
| 0.518465 | 2.807533 |
| 0.522477 | 2.801518 |
| 0.526521 | 2.795645 |
| 0.530595 | 2.78991 |
| 0.534701 | 2.784307 |
| 0.538839 | 2.778835 |
| 0.543009 | 2.773487 |
| 0.547211 | 2.768262 |
| 0.551445 | 2.763155 |
| 0.555713 | 2.758163 |
| 0.560013 | 2.753282 |
| 0.564347 | 2.74851 |
| 0.568714 | 2.743844 |
| 0.573115 | 2.73928 |
| 0.57755 | 2.734815 |
| 0.582019 | 2.730448 |
| 0.586523 | 2.726174 |
| 0.591062 | 2.721993 |
| 0.595636 | 2.7179 |
| 0.600245 | 2.713895 |
| 0.60489 | 2.709974 |
| 0.609571 | 2.706135 |
| 0.614289 | 2.702377 |
| 0.619042 | 2.698697 |
| 0.623833 | 2.695093 |
| 0.62866 | 2.691563 |
| 0.633525 | 2.688106 |
| 0.638428 | 2.684719 |
| 0.643368 | 2.681401 |
| 0.648347 | 2.67815 |
| 0.653364 | 2.674965 |
| 0.65842 | 2.671843 |
| 0.663515 | 2.668784 |
| 0.66865 | 2.665785 |
| 0.673824 | 2.662846 |
| 0.679039 | 2.659964 |
| 0.684293 | 2.65714 |
| 0.689589 | 2.65437 |
| 0.694925 | 2.651654 |
| 0.700303 | 2.648991 |
| 0.705722 | 2.64638 |
| 0.711183 | 2.643819 |
| 0.716687 | 2.641306 |
| 0.722233 | 2.638842 |
| 0.727822 | 2.636425 |
| 0.733454 | 2.634054 |
| 0.73913 | 2.631727 |
| 0.74485 | 2.629444 |
| 0.750614 | 2.627205 |
| 0.756422 | 2.625007 |
| 0.762276 | 2.62285 |
| 0.768175 | 2.620733 |
| 0.774119 | 2.618656 |
| 0.78011 | 2.616617 |
| 0.786147 | 2.614615 |
| 0.79223 | 2.61265 |
| 0.798361 | 2.610722 |
| 0.804539 | 2.608828 |
| 0.810765 | 2.606969 |
| 0.817039 | 2.605144 |
| 0.823362 | 2.603351 |
| 0.829733 | 2.601592 |
| 0.836154 | 2.599863 |
| 0.842625 | 2.598166 |
| 0.849146 | 2.5965 |
| 0.855717 | 2.594863 |
| 0.862339 | 2.593255 |
| 0.869012 | 2.591676 |
| 0.875737 | 2.590125 |
| 0.882514 | 2.588601 |
| 0.889343 | 2.587104 |
| 0.896225 | 2.585634 |
| 0.90316 | 2.584189 |
| 0.91015 | 2.58277 |
| 0.917193 | 2.581375 |
| 0.92429 | 2.580005 |
| 0.931443 | 2.578658 |
| 0.938651 | 2.577335 |
| 0.945915 | 2.576035 |
| 0.953235 | 2.574758 |
| 0.960611 | 2.573502 |
| 0.968045 | 2.572268 |
| 0.975536 | 2.571056 |
| 0.983085 | 2.569864 |
| 0.990693 | 2.568692 |
| 0.99836 | 2.567541 |
| 1.00609 | 2.566409 |
| 1.01387 | 2.565296 |
| 1.02172 | 2.564202 |
| 1.02962 | 2.563127 |
| 1.03759 | 2.56207 |
| 1.04562 | 2.561031 |
| 1.05371 | 2.560009 |
| 1.06187 | 2.559005 |
| 1.07008 | 2.558017 |
| 1.07836 | 2.557046 |
| 1.08671 | 2.556091 |
| 1.09512 | 2.555152 |
| 1.10359 | 2.554229 |
| 1.11213 | 2.553321 |
| 1.12074 | 2.552428 |
| 1.12941 | 2.55155 |
| 1.13815 | 2.550687 |
| 1.14696 | 2.549838 |
| 1.15584 | 2.549002 |
| 1.16478 | 2.548181 |
| 1.17379 | 2.547373 |
| 1.18288 | 2.546578 |
| 1.19203 | 2.545797 |
| 1.20126 | 2.545028 |
| 1.21055 | 2.544272 |
| 1.21992 | 2.543528 |
| 1.22936 | 2.542796 |
| 1.23887 | 2.542076 |
| 1.24846 | 2.541367 |
| 1.25812 | 2.54067 |
| 1.26786 | 2.539985 |
| 1.27767 | 2.53931 |
| 1.28756 | 2.538647 |
| 1.29752 | 2.537994 |
| 1.30756 | 2.537351 |
| 1.31768 | 2.536719 |
| 1.32788 | 2.536097 |
| 1.33815 | 2.535485 |
| 1.34851 | 2.534883 |
| 1.35894 | 2.53429 |
| 1.36946 | 2.533707 |
| 1.38006 | 2.533133 |
| 1.39074 | 2.532568 |
| 1.4015 | 2.532012 |
| 1.41234 | 2.531464 |
| 1.42327 | 2.530926 |
| 1.43429 | 2.530396 |
| 1.44539 | 2.529874 |
| 1.45657 | 2.52936 |
| 1.46784 | 2.528855 |
| 1.4792 | 2.528357 |
| 1.49065 | 2.527867 |
| 1.50218 | 2.527385 |
| 1.51381 | 2.52691 |
| 1.52552 | 2.526443 |
| 1.53733 | 2.525983 |
| 1.54922 | 2.52553 |
| 1.56121 | 2.525084 |
| 1.57329 | 2.524645 |
| 1.58547 | 2.524212 |
| 1.59774 | 2.523786 |
| 1.6101 | 2.523367 |
| 1.62256 | 2.522954 |
| 1.63512 | 2.522548 |
| 1.64777 | 2.522147 |
| 1.66052 | 2.521753 |
| 1.67337 | 2.521365 |
| 1.68632 | 2.520982 |
| 1.69937 | 2.520606 |
| 1.71252 | 2.520235 |
| 1.72578 | 2.519869 |
| 1.73913 | 2.519509 |
| 1.75259 | 2.519154 |
| 1.76615 | 2.518805 |
| 1.77982 | 2.518461 |
| 1.79359 | 2.518122 |
| 1.80747 | 2.517788 |
| 1.82146 | 2.517459 |
| 1.83555 | 2.517134 |
| 1.84976 | 2.516815 |
| 1.86407 | 2.5165 |
| 1.8785 | 2.51619 |
| 1.89303 | 2.515884 |
| 1.90768 | 2.515582 |
| 1.92245 | 2.515285 |
| 1.93732 | 2.514992 |
| 1.95232 | 2.514704 |
| 1.96742 | 2.514419 |
| 1.98265 | 2.514139 |
| 1.99799 | 2.513862 |
| 2.01345 | 2.51359 |
| 2.02903 | 2.513321 |
| 2.04473 | 2.513056 |
| 2.06056 | 2.512795 |
| 2.0765 | 2.512537 |
| 2.09257 | 2.512283 |
| 2.10877 | 2.512032 |
| 2.12508 | 2.511785 |
| 2.14153 | 2.511541 |
| 2.1581 | 2.511301 |
| 2.1748 | 2.511064 |
| 2.19163 | 2.510829 |
| 2.20859 | 2.510598 |
| 2.22568 | 2.51037 |
| 2.24291 | 2.510146 |
| 2.26026 | 2.509924 |
| 2.27775 | 2.509705 |
| 2.29538 | 2.509488 |
| 2.31314 | 2.509275 |
| 2.33104 | 2.509064 |
| 2.34908 | 2.508856 |
| 2.36726 | 2.508651 |
| 2.38558 | 2.508448 |
| 2.40404 | 2.508247 |
| 2.42264 | 2.508049 |
| 2.44139 | 2.507854 |
| 2.46028 | 2.507661 |
| 2.47932 | 2.50747 |
| 2.49851 | 2.507282 |
| 2.51784 | 2.507095 |
| 2.53733 | 2.506911 |
| 2.55696 | 2.506729 |
| 2.57675 | 2.506549 |
| 2.59669 | 2.506372 |
| 2.61679 | 2.506196 |
| 2.63704 | 2.506022 |
| 2.65744 | 2.50585 |
| 2.67801 | 2.50568 |
| 2.69873 | 2.505512 |
| 2.71962 | 2.505345 |
| 2.74066 | 2.50518 |
| 2.76187 | 2.505017 |
| 2.78324 | 2.504856 |
| 2.80478 | 2.504696 |
| 2.82649 | 2.504538 |
| 2.84836 | 2.504382 |
| 2.8704 | 2.504226 |
| 2.89261 | 2.504073 |
| 2.915 | 2.503921 |
| 2.93755 | 2.50377 |
| 2.96029 | 2.50362 |
| 2.9832 | 2.503472 |
| 3.00628 | 2.503325 |
| 3.02954 | 2.50318 |
| 3.05299 | 2.503035 |
| 3.07661 | 2.502892 |
| 3.10042 | 2.50275 |
| 3.12442 | 2.502609 |
| 3.14859 | 2.502469 |
| 3.17296 | 2.50233 |
| 3.19751 | 2.502192 |
| 3.22226 | 2.502055 |
| 3.24719 | 2.501919 |
| 3.27232 | 2.501784 |
| 3.29764 | 2.50165 |
| 3.32316 | 2.501516 |
| 3.34888 | 2.501384 |
| 3.37479 | 2.501252 |
| 3.40091 | 2.501121 |
| 3.42723 | 2.50099 |
| 3.45375 | 2.500861 |
| 3.48048 | 2.500732 |
| 3.50741 | 2.500603 |
| 3.53455 | 2.500475 |
| 3.5619 | 2.500348 |
| 3.58947 | 2.500221 |
| 3.61724 | 2.500094 |
| 3.64524 | 2.499968 |
| 3.67345 | 2.499843 |
| 3.70187 | 2.499718 |
| 3.73052 | 2.499593 |
| 3.75939 | 2.499468 |
| 3.78848 | 2.499344 |
| 3.8178 | 2.49922 |
| 3.84734 | 2.499096 |
| 3.87711 | 2.498973 |
| 3.90712 | 2.49885 |
| 3.93735 | 2.498726 |
| 3.96782 | 2.498603 |
| 3.99853 | 2.49848 |
| 4.02947 | 2.498357 |
| 4.06065 | 2.498234 |
| 4.09207 | 2.498111 |
| 4.12374 | 2.497988 |
| 4.15565 | 2.497865 |
| 4.18781 | 2.497742 |
| 4.22022 | 2.497618 |
| 4.25288 | 2.497495 |
| 4.28579 | 2.497371 |
| 4.31895 | 2.497247 |
| 4.35237 | 2.497123 |
| 4.38606 | 2.496998 |
| 4.42 | 2.496874 |
| 4.4542 | 2.496748 |
| 4.48867 | 2.496623 |
| 4.52341 | 2.496497 |
| 4.55841 | 2.49637 |
| 4.59369 | 2.496243 |
| 4.62923 | 2.496116 |
| 4.66506 | 2.495988 |
| 4.70116 | 2.495859 |
| 4.73754 | 2.49573 |
| 4.7742 | 2.4956 |
| 4.81114 | 2.495469 |
| 4.84837 | 2.495338 |
| 4.88589 | 2.495206 |
| 4.9237 | 2.495073 |
| 4.96181 | 2.49494 |
| 5.0002 | 2.494805 |
| 5.0389 | 2.49467 |
| 5.07789 | 2.494533 |
| 5.11719 | 2.494396 |
| 5.15678 | 2.494258 |
| 5.19669 | 2.494118 |
| 5.23691 | 2.493978 |
| 5.27743 | 2.493837 |
| 5.31827 | 2.493694 |
| 5.35943 | 2.49355 |
| 5.4009 | 2.493405 |
| 5.44269 | 2.493259 |
| 5.48481 | 2.493111 |
| 5.52726 | 2.492962 |
| 5.57003 | 2.492812 |
| 5.61313 | 2.49266 |
| 5.65657 | 2.492507 |
| 5.70034 | 2.492353 |
| 5.74446 | 2.492196 |
| 5.78891 | 2.492039 |
| 5.83371 | 2.491879 |
| 5.87885 | 2.491718 |
| 5.92434 | 2.491555 |
| 5.97019 | 2.491391 |
| 6.01639 | 2.491225 |
| 6.06295 | 2.491056 |
| 6.10987 | 2.490886 |
| 6.15715 | 2.490714 |
| 6.20479 | 2.49054 |
| 6.25281 | 2.490364 |
| 6.3012 | 2.490186 |
| 6.34996 | 2.490006 |
| 6.3991 | 2.489823 |
| 6.44862 | 2.489639 |
| 6.49852 | 2.489452 |
| 6.54881 | 2.489262 |
| 6.59949 | 2.489071 |
| 6.65056 | 2.488877 |
| 6.70202 | 2.48868 |
| 6.75389 | 2.488481 |
| 6.80615 | 2.488279 |
| 6.85882 | 2.488074 |
| 6.9119 | 2.487867 |
| 6.96539 | 2.487657 |
| 7.01929 | 2.487444 |
| 7.07361 | 2.487228 |
| 7.12834 | 2.487009 |
| 7.18351 | 2.486787 |
| 7.2391 | 2.486562 |
| 7.29512 | 2.486334 |
| 7.35157 | 2.486103 |
| 7.40846 | 2.485868 |
| 7.46579 | 2.48563 |
| 7.52356 | 2.485388 |
| 7.58179 | 2.485143 |
| 7.64046 | 2.484894 |
| 7.69958 | 2.484642 |
| 7.75917 | 2.484386 |
| 7.81921 | 2.484126 |
| 7.87972 | 2.483862 |
| 7.9407 | 2.483593 |
| 8.00215 | 2.483321 |
| 8.06407 | 2.483045 |
| 8.12647 | 2.482764 |
| 8.18936 | 2.48248 |
| 8.25273 | 2.48219 |
| 8.3166 | 2.481896 |
| 8.38096 | 2.481598 |
| 8.44581 | 2.481294 |
| 8.51117 | 2.480986 |
| 8.57703 | 2.480673 |
| 8.64341 | 2.480355 |
| 8.71029 | 2.480032 |
| 8.7777 | 2.479703 |
| 8.84562 | 2.47937 |
| 8.91408 | 2.47903 |
| 8.98306 | 2.478685 |
| 9.05257 | 2.478335 |
| 9.12263 | 2.477978 |
| 9.19322 | 2.477616 |
| 9.26436 | 2.477247 |
| 9.33606 | 2.476873 |
| 9.4083 | 2.476492 |
| 9.48111 | 2.476104 |
| 9.55448 | 2.47571 |
| 9.62842 | 2.475309 |
| 9.70293 | 2.474901 |
| 9.77801 | 2.474487 |
| 9.85368 | 2.474065 |
| 9.92993 | 2.473635 |
| 10.0068 | 2.473199 |
| 10.0842 | 2.472754 |
| 10.1622 | 2.472302 |
| 10.2409 | 2.471841 |
| 10.3201 | 2.471373 |
| 10.4 | 2.470896 |
Optical transmission calculator
Free-standing sample in vacuum, normal incidence- Transmittance T
- —
- Reflectance R
- —
Fresnel reflection calculator
- Rp
- —
- Rs
- —
- R = (Rp+Rs)/2
- —
- Phase φp
- —
- Phase φs
- —
- Brewster angle θB
- —
- Critical angle θC
- —
nγ; room temperature.