Optical constants
Refractive index of Al2O3 (Aluminium sesquioxide, Sapphire, Alumina)
Malitson and Dodge 1972: α-Al2O3 (Sapphire); n(o) 0.20–5.0 µm
- Data
- formula 1
- Range
- 0.2–5 µm
- Temperature
- 293 K
- Optical axis
- o
- State
- crystalline
- Licence
- CC0-1.0
Plot
Click the plot to set the calculator wavelength.
At one wavelength
- Refractive index n
- 1.76817
- Extinction coefficient k
- 0
- Permittivity ε1
- 3.12643
- Permittivity ε2
- 0
- Absorption coefficient α
- 0 cm⁻¹
- Penetration depth δ = λ/(2πk)
- — nm
- Abbe number Vd
- 72.309
- Chromatic dispersion dn/dλ
- -0.055289 µm⁻¹
- Group index ng
- 1.80066
- Group velocity dispersion
- 91.1743 fs²/mm
- Dispersion parameter D
- -497.404 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
# Al2O3 (Aluminium sesquioxide, Sapphire, Alumina): Malitson and Dodge 1972: α-Al2O3 (Sapphire); n(o) 0.20–5.0 µm
al2o3 = ls.fetch_refractiveindex("main", "Al2O3", "Malitson-o", ref="c5c2f188e848453def5970e347399d653df2ffc2")
print(al2o3.range_nm) # (200, 5000) nm
eps = al2o3.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_de7f983cd237/lightsmith"
al2o3 = ls.Tabulated.model_validate(json.load(urllib.request.urlopen(url)))
print(al2o3.source) # citation and provenance travel with the data
Any dataset here, as the library's Tabulated material (al2o3/malitson-dodge-1972-o).
# ... load al2o3 as above, then:
sim = ls.Simulation(
particles=[ls.Particle(shape=ls.Sphere(radius_nm=50), material=al2o3)],
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"]).
import json, urllib.request
import lightsmith as ls
url = "https://materials.lightsmith.dev/v1/datasets/ds_de7f983cd237/lightsmith?model=drude_lorentz"
al2o3_dl = ls.DrudeLorentz.model_validate(json.load(urllib.request.urlopen(url)))
A dispersive Drude–Lorentz model for time-domain solvers.
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
Sellmeier (formula 1), λ in µmValid from 0.2 to 5.0 µm.
Coefficients as stored
| Ci | Value |
|---|---|
| C1 | 0.0 |
| C2 | 1.4313493 |
| C3 | 0.0726631 |
| C4 | 0.65054713 |
| C5 | 0.1193242 |
| C6 | 5.3414021 |
| C7 | 18.028251 |
Comments and conditions
Conditions
- temperature
- 293 K
- direction
- o
References
2) M. J. Dodge. "Refractive index" in Handbook of Laser Science and Technology, Volume IV, Optical Materials: Part 2, CRC Press, Boca Raton, 1986, p. 30
* Ref. 1 is a talk abstract in a conference program; Ref. 2 provides a dispersion formula
Cite
I. H. Malitson and M. J. Dodge. Refractive index and birefringence of synthetic sapphire. J. Opt. Soc. Am. 62, 1405 (1972); 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 |
|---|---|
| 0.2 | 1.912709 |
| 0.20162 | 1.909342 |
| 0.203253 | 1.906066 |
| 0.204899 | 1.90288 |
| 0.206559 | 1.899779 |
| 0.208232 | 1.896761 |
| 0.209919 | 1.893822 |
| 0.211619 | 1.890959 |
| 0.213333 | 1.88817 |
| 0.215061 | 1.885453 |
| 0.216803 | 1.882804 |
| 0.21856 | 1.880221 |
| 0.22033 | 1.877703 |
| 0.222115 | 1.875247 |
| 0.223914 | 1.87285 |
| 0.225727 | 1.870512 |
| 0.227556 | 1.86823 |
| 0.229399 | 1.866002 |
| 0.231257 | 1.863827 |
| 0.23313 | 1.861704 |
| 0.235019 | 1.859629 |
| 0.236922 | 1.857603 |
| 0.238841 | 1.855623 |
| 0.240776 | 1.853688 |
| 0.242726 | 1.851797 |
| 0.244692 | 1.849948 |
| 0.246674 | 1.848141 |
| 0.248672 | 1.846374 |
| 0.250687 | 1.844646 |
| 0.252717 | 1.842956 |
| 0.254764 | 1.841303 |
| 0.256828 | 1.839685 |
| 0.258908 | 1.838102 |
| 0.261005 | 1.836554 |
| 0.263119 | 1.835038 |
| 0.265251 | 1.833554 |
| 0.267399 | 1.832102 |
| 0.269565 | 1.83068 |
| 0.271748 | 1.829287 |
| 0.27395 | 1.827924 |
| 0.276169 | 1.826588 |
| 0.278406 | 1.82528 |
| 0.280661 | 1.823999 |
| 0.282934 | 1.822744 |
| 0.285226 | 1.821514 |
| 0.287536 | 1.820309 |
| 0.289865 | 1.819128 |
| 0.292213 | 1.817971 |
| 0.29458 | 1.816836 |
| 0.296966 | 1.815724 |
| 0.299371 | 1.814634 |
| 0.301796 | 1.813566 |
| 0.304241 | 1.812518 |
| 0.306705 | 1.81149 |
| 0.30919 | 1.810483 |
| 0.311694 | 1.809495 |
| 0.314219 | 1.808526 |
| 0.316764 | 1.807575 |
| 0.31933 | 1.806643 |
| 0.321916 | 1.805728 |
| 0.324524 | 1.804831 |
| 0.327152 | 1.80395 |
| 0.329802 | 1.803086 |
| 0.332474 | 1.802238 |
| 0.335167 | 1.801406 |
| 0.337882 | 1.80059 |
| 0.340618 | 1.799788 |
| 0.343377 | 1.799001 |
| 0.346159 | 1.798229 |
| 0.348963 | 1.797471 |
| 0.351789 | 1.796727 |
| 0.354639 | 1.795996 |
| 0.357511 | 1.795279 |
| 0.360407 | 1.794574 |
| 0.363326 | 1.793882 |
| 0.366269 | 1.793203 |
| 0.369236 | 1.792536 |
| 0.372227 | 1.79188 |
| 0.375242 | 1.791236 |
| 0.378282 | 1.790604 |
| 0.381346 | 1.789983 |
| 0.384434 | 1.789372 |
| 0.387548 | 1.788773 |
| 0.390688 | 1.788184 |
| 0.393852 | 1.787605 |
| 0.397042 | 1.787036 |
| 0.400258 | 1.786477 |
| 0.4035 | 1.785927 |
| 0.406769 | 1.785387 |
| 0.410064 | 1.784857 |
| 0.413385 | 1.784335 |
| 0.416734 | 1.783822 |
| 0.420109 | 1.783318 |
| 0.423512 | 1.782822 |
| 0.426942 | 1.782335 |
| 0.430401 | 1.781856 |
| 0.433887 | 1.781385 |
| 0.437401 | 1.780921 |
| 0.440944 | 1.780465 |
| 0.444516 | 1.780017 |
| 0.448116 | 1.779577 |
| 0.451746 | 1.779143 |
| 0.455405 | 1.778716 |
| 0.459094 | 1.778297 |
| 0.462813 | 1.777884 |
| 0.466562 | 1.777478 |
| 0.470341 | 1.777078 |
| 0.47415 | 1.776685 |
| 0.477991 | 1.776298 |
| 0.481863 | 1.775917 |
| 0.485766 | 1.775542 |
| 0.489701 | 1.775173 |
| 0.493667 | 1.77481 |
| 0.497666 | 1.774453 |
| 0.501697 | 1.774101 |
| 0.505761 | 1.773754 |
| 0.509857 | 1.773413 |
| 0.513987 | 1.773077 |
| 0.51815 | 1.772746 |
| 0.522347 | 1.77242 |
| 0.526578 | 1.772098 |
| 0.530844 | 1.771782 |
| 0.535144 | 1.77147 |
| 0.539478 | 1.771163 |
| 0.543848 | 1.770861 |
| 0.548253 | 1.770563 |
| 0.552694 | 1.770269 |
| 0.557171 | 1.769979 |
| 0.561684 | 1.769694 |
| 0.566234 | 1.769412 |
| 0.57082 | 1.769135 |
| 0.575444 | 1.768861 |
| 0.580105 | 1.768592 |
| 0.584804 | 1.768326 |
| 0.58954 | 1.768063 |
| 0.594316 | 1.767804 |
| 0.59913 | 1.767549 |
| 0.603983 | 1.767297 |
| 0.608875 | 1.767048 |
| 0.613807 | 1.766803 |
| 0.618779 | 1.766561 |
| 0.623791 | 1.766322 |
| 0.628843 | 1.766085 |
| 0.633937 | 1.765852 |
| 0.639072 | 1.765622 |
| 0.644248 | 1.765395 |
| 0.649467 | 1.76517 |
| 0.654727 | 1.764948 |
| 0.660031 | 1.764729 |
| 0.665377 | 1.764512 |
| 0.670766 | 1.764298 |
| 0.6762 | 1.764086 |
| 0.681677 | 1.763877 |
| 0.687198 | 1.76367 |
| 0.692765 | 1.763465 |
| 0.698376 | 1.763263 |
| 0.704033 | 1.763063 |
| 0.709736 | 1.762864 |
| 0.715484 | 1.762668 |
| 0.72128 | 1.762474 |
| 0.727122 | 1.762282 |
| 0.733012 | 1.762091 |
| 0.738949 | 1.761902 |
| 0.744935 | 1.761716 |
| 0.750969 | 1.76153 |
| 0.757052 | 1.761347 |
| 0.763184 | 1.761165 |
| 0.769365 | 1.760985 |
| 0.775597 | 1.760806 |
| 0.78188 | 1.760629 |
| 0.788213 | 1.760453 |
| 0.794597 | 1.760278 |
| 0.801034 | 1.760105 |
| 0.807522 | 1.759933 |
| 0.814063 | 1.759762 |
| 0.820657 | 1.759593 |
| 0.827304 | 1.759424 |
| 0.834005 | 1.759257 |
| 0.840761 | 1.75909 |
| 0.847571 | 1.758925 |
| 0.854436 | 1.758761 |
| 0.861357 | 1.758597 |
| 0.868334 | 1.758434 |
| 0.875368 | 1.758272 |
| 0.882458 | 1.758111 |
| 0.889606 | 1.757951 |
| 0.896812 | 1.757791 |
| 0.904076 | 1.757632 |
| 0.911399 | 1.757473 |
| 0.918781 | 1.757315 |
| 0.926223 | 1.757158 |
| 0.933726 | 1.757001 |
| 0.941289 | 1.756844 |
| 0.948913 | 1.756688 |
| 0.9566 | 1.756532 |
| 0.964348 | 1.756376 |
| 0.972159 | 1.756221 |
| 0.980034 | 1.756066 |
| 0.987972 | 1.75591 |
| 0.995974 | 1.755756 |
| 1.00404 | 1.755601 |
| 1.01217 | 1.755446 |
| 1.02037 | 1.755291 |
| 1.02864 | 1.755136 |
| 1.03697 | 1.754981 |
| 1.04537 | 1.754826 |
| 1.05384 | 1.754671 |
| 1.06237 | 1.754515 |
| 1.07098 | 1.754359 |
| 1.07965 | 1.754203 |
| 1.0884 | 1.754047 |
| 1.09721 | 1.75389 |
| 1.1061 | 1.753733 |
| 1.11506 | 1.753575 |
| 1.12409 | 1.753416 |
| 1.1332 | 1.753258 |
| 1.14238 | 1.753098 |
| 1.15163 | 1.752938 |
| 1.16096 | 1.752777 |
| 1.17036 | 1.752616 |
| 1.17984 | 1.752454 |
| 1.1894 | 1.752291 |
| 1.19903 | 1.752127 |
| 1.20875 | 1.751962 |
| 1.21854 | 1.751796 |
| 1.22841 | 1.751629 |
| 1.23836 | 1.751461 |
| 1.24839 | 1.751292 |
| 1.2585 | 1.751122 |
| 1.26869 | 1.750951 |
| 1.27897 | 1.750779 |
| 1.28933 | 1.750605 |
| 1.29977 | 1.75043 |
| 1.3103 | 1.750253 |
| 1.32091 | 1.750075 |
| 1.33161 | 1.749896 |
| 1.3424 | 1.749715 |
| 1.35327 | 1.749533 |
| 1.36423 | 1.749349 |
| 1.37528 | 1.749163 |
| 1.38642 | 1.748976 |
| 1.39765 | 1.748787 |
| 1.40898 | 1.748596 |
| 1.42039 | 1.748403 |
| 1.43189 | 1.748208 |
| 1.44349 | 1.748012 |
| 1.45518 | 1.747813 |
| 1.46697 | 1.747612 |
| 1.47885 | 1.747409 |
| 1.49083 | 1.747204 |
| 1.50291 | 1.746997 |
| 1.51508 | 1.746787 |
| 1.52735 | 1.746575 |
| 1.53972 | 1.74636 |
| 1.5522 | 1.746143 |
| 1.56477 | 1.745924 |
| 1.57744 | 1.745702 |
| 1.59022 | 1.745477 |
| 1.6031 | 1.74525 |
| 1.61609 | 1.745019 |
| 1.62918 | 1.744786 |
| 1.64237 | 1.74455 |
| 1.65568 | 1.744311 |
| 1.66909 | 1.744069 |
| 1.68261 | 1.743824 |
| 1.69624 | 1.743576 |
| 1.70998 | 1.743324 |
| 1.72383 | 1.743069 |
| 1.73779 | 1.742811 |
| 1.75187 | 1.742549 |
| 1.76606 | 1.742284 |
| 1.78036 | 1.742015 |
| 1.79478 | 1.741742 |
| 1.80932 | 1.741466 |
| 1.82397 | 1.741186 |
| 1.83875 | 1.740902 |
| 1.85364 | 1.740613 |
| 1.86866 | 1.740321 |
| 1.88379 | 1.740025 |
| 1.89905 | 1.739724 |
| 1.91443 | 1.739419 |
| 1.92994 | 1.73911 |
| 1.94557 | 1.738796 |
| 1.96133 | 1.738477 |
| 1.97722 | 1.738154 |
| 1.99324 | 1.737826 |
| 2.00938 | 1.737493 |
| 2.02566 | 1.737156 |
| 2.04206 | 1.736813 |
| 2.0586 | 1.736465 |
| 2.07528 | 1.736111 |
| 2.09209 | 1.735753 |
| 2.10904 | 1.735388 |
| 2.12612 | 1.735019 |
| 2.14334 | 1.734643 |
| 2.1607 | 1.734262 |
| 2.1782 | 1.733875 |
| 2.19585 | 1.733481 |
| 2.21363 | 1.733082 |
| 2.23156 | 1.732676 |
| 2.24964 | 1.732264 |
| 2.26786 | 1.731846 |
| 2.28623 | 1.731421 |
| 2.30475 | 1.730989 |
| 2.32342 | 1.73055 |
| 2.34224 | 1.730104 |
| 2.36121 | 1.729651 |
| 2.38033 | 1.729191 |
| 2.39962 | 1.728724 |
| 2.41905 | 1.728248 |
| 2.43865 | 1.727766 |
| 2.4584 | 1.727275 |
| 2.47831 | 1.726776 |
| 2.49839 | 1.726269 |
| 2.51862 | 1.725754 |
| 2.53902 | 1.725231 |
| 2.55959 | 1.724698 |
| 2.58032 | 1.724157 |
| 2.60122 | 1.723607 |
| 2.62229 | 1.723048 |
| 2.64353 | 1.72248 |
| 2.66495 | 1.721902 |
| 2.68653 | 1.721314 |
| 2.70829 | 1.720717 |
| 2.73023 | 1.72011 |
| 2.75235 | 1.719492 |
| 2.77464 | 1.718864 |
| 2.79711 | 1.718226 |
| 2.81977 | 1.717576 |
| 2.84261 | 1.716916 |
| 2.86564 | 1.716244 |
| 2.88885 | 1.715561 |
| 2.91225 | 1.714866 |
| 2.93584 | 1.71416 |
| 2.95962 | 1.713441 |
| 2.98359 | 1.71271 |
| 3.00776 | 1.711966 |
| 3.03212 | 1.71121 |
| 3.05668 | 1.71044 |
| 3.08144 | 1.709657 |
| 3.1064 | 1.70886 |
| 3.13156 | 1.70805 |
| 3.15693 | 1.707225 |
| 3.1825 | 1.706387 |
| 3.20827 | 1.705533 |
| 3.23426 | 1.704664 |
| 3.26046 | 1.70378 |
| 3.28687 | 1.702881 |
| 3.31349 | 1.701966 |
| 3.34033 | 1.701034 |
| 3.36739 | 1.700086 |
| 3.39466 | 1.699121 |
| 3.42216 | 1.698139 |
| 3.44988 | 1.697139 |
| 3.47782 | 1.696122 |
| 3.50599 | 1.695086 |
| 3.53439 | 1.694032 |
| 3.56302 | 1.692958 |
| 3.59188 | 1.691866 |
| 3.62098 | 1.690753 |
| 3.65031 | 1.68962 |
| 3.67987 | 1.688467 |
| 3.70968 | 1.687293 |
| 3.73973 | 1.686097 |
| 3.77002 | 1.68488 |
| 3.80056 | 1.68364 |
| 3.83134 | 1.682377 |
| 3.86238 | 1.681091 |
| 3.89366 | 1.679781 |
| 3.9252 | 1.678447 |
| 3.95699 | 1.677088 |
| 3.98905 | 1.675704 |
| 4.02136 | 1.674294 |
| 4.05393 | 1.672857 |
| 4.08677 | 1.671394 |
| 4.11987 | 1.669903 |
| 4.15324 | 1.668384 |
| 4.18688 | 1.666836 |
| 4.22079 | 1.665259 |
| 4.25498 | 1.663651 |
| 4.28945 | 1.662013 |
| 4.32419 | 1.660344 |
| 4.35922 | 1.658642 |
| 4.39453 | 1.656908 |
| 4.43012 | 1.65514 |
| 4.46601 | 1.653338 |
| 4.50218 | 1.651501 |
| 4.53865 | 1.649628 |
| 4.57541 | 1.647718 |
| 4.61247 | 1.645771 |
| 4.64983 | 1.643785 |
| 4.6875 | 1.641761 |
| 4.72547 | 1.639696 |
| 4.76374 | 1.637589 |
| 4.80233 | 1.635441 |
| 4.84123 | 1.63325 |
| 4.88044 | 1.631014 |
| 4.91997 | 1.628733 |
| 4.95983 | 1.626406 |
| 5 | 1.624032 |
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
- —
Synthetic sapphire, Ordinary ray (o), 20 °C